Guarantee Mortgage - San Francisco, 505 Montgomery

We have helped Bay Area families finance their home purchase, with over $2 billion in loans annually, and we can help you.

Offering a wide range of products and services, Guarantee Mortgage is well prepared to meet every real estate lending need.

We have 22 years under our belt providing world-class client service. Our top priority is to make sure you are presented with all available loan options, so that you can make an informed decision, that’s right for your financial situation.

Guarantee Mortgage NMLS #1850 and CAL-BRE License #01215943


Recommendations (1448)

Mar 8, 2023

Irving B. recommends Orlando Diaz

Orlando was an absolute amazing loan officer. His professionalism is unmatched. I really don’t know if I could have done it without him. Thank you Orlando. Truly appreciate you.
Mar 5, 2023

Sam Brown recommends Orlando Diaz

Orlando was fantastic. I truly do t know if I would have been able to buy my house without him. He executed the transaction flawlessly and efficiently.

For the record. I was a mortgage loan officer for 10 years. And now when it came time for me to do a mortgage for myself personally. And I had a chance to choose my own loan officer to work with. I chose Orlando.

Thanks Orlando. Really appreciate you.
Mar 1, 2023

William P. recommends Larry Horowitz

I have known Larry personally for over 30 years and he has helped me with mortgages on numerous properties. I have obtained mortgages for purchase as well as refi and cash out refi's. Larry always find the best option for whatever my needs are at that time. Sometimes my investment horizon is short term, sometimes longer, and not all mortgages are the same. Larry's expertise and professionalism have always served me well. He's smart, honest, and I trust him.

I'd never apply for a mortgage without Larry. I highly recommend him and his company. I've always been impressed.
Feb 13, 2023

Karen Castillo S. recommends Kathy Derangi

Kathy was the best at providing information, answering questions, providing different scenarios, and guiding us throughout the purchase process. I am very pleased with our experience.
Feb 8, 2023

Curtis M. recommends Kathy Derangi

Kathy was very helpful and always answered her phone. She was able to give us a few different scenarios and guided us through the process smoothly. Love the positive attitude and great advice!
Feb 2, 2023

Heather B. recommends James W. Argo

James has helped us several times and every time has been 5 stars. Thank you!
Jan 30, 2023

Thaddeus B. recommends James W. Argo

Great service, spot on with getting everything in line to keep the ball moving.
Jan 23, 2023

Lisa C. recommends Orlando Diaz

Working with Orlando and the Guarantee Mortgage team was a great experience! Orlando was available to answer all of our questions and kept us thoroughly informed as we progressed through the loan process. He helped us navigate our unique situations and was very easy to work with throughout.
Jan 3, 2023

Jeffrey E. recommends Larry Horowitz

Our fifth loan with Larry. He makes it all seem easy.
Jan 3, 2023

Nick B. recommends Orlando Diaz

Orlando was incredibly helpful through every step of the process. He came very highly recommended to us and once we reached out he got to work right away and had us through the process quickly and easily. He was there to answer our calls whenever we had questions and would walk us through the documents and explain the breakdowns. From start to finish he was only a phone call / email away and made sure there were no surprises and we ended up completing our signing early. I would highly recommend Orlando!
Dec 13, 2022

Anthony R. recommends Kathy Derangi

Kathy did a great job. She goes above and beyond and is very diligent and responsive while working on your loan.
Dec 8, 2022

Felicia G. recommends Larry Horowitz

Larry Horowitz is an exceptional loan consultant. I have worked with him for over 20 years and with each transaction he communicates clearly what is needed and ensures the process goes smoothly. Larry is always positive and professional. I know that I will get the best loan for me when I work with Larry.
Nov 9, 2022

Den Prom recommends Pov Oum

Nothing to complain about, and that is a really good thing.
Oct 20, 2022

Tim Lew recommends Ming Leong

We had a tight timeline and complex mortgage. Ming was helpful and communicative through the entire process. He helped us navigate a gauntlet of information.
Oct 11, 2022

Yi Mon recommends Pov Oum

Pov Oum is very good.
Oct 9, 2022

Katherine Harry recommends Pov Oum

Pov is an excellent loan officer who helped my partner and I purchase our first home in the Bay Area. She is incredibly responsive and worked patiently with us as we searched for a home in a changing economic environment. She clearly explained our options to us along the way. Her hard work allowed us to close on our house in 17 days! I highly recommend Pov Oum to anyone searching for a quality loan officer.
Sep 28, 2022

Taylor Davis recommends Kathy Derangi

Kathy will call seller’s agents and make sure you win in a competitive bid situation. Super fast and responsive. Can get closed on very tight timelines. AWESOME!!
Sep 18, 2022

mauricio castillo recommends Pov Oum

Accounts Manager.

Where do we begin! Pov is simply the best in the business. Her talent, professionalism and dedication is admirable. She never looses focus of her clients dreams and goals. She helped us accomplish something that seemed impossible. We are forever grateful for help and look forward to working with her in our next adventure. Not only do we recommend her, we urge you to find someone as caring and dedicated as her. Thank you Pov!

Best Regards,

The Castillo Family.
Sep 13, 2022

Seif F. recommends Robin Patronik

Robin was very clear and concise throughout the whole process. Explained all the options clearly so I can decide on the best possible situation for myself. Very knowledgeable. Offered her advise and was very timely in response.
Sep 12, 2022

Madeleine F Fortich recommends Katie Perez


Katie Perez is my go-to loan officer. I started out as a loan officer and hold my LO to a higher standard than probably most realtors. Katie is the consummate loan officer due to her diligence on files and more importantly her soft skills with clients. I know that her ability to navigate through what the client says VS. what the client shows with paperwork can be two different things. She has the ability to flag potential pitfalls and the savviness to suggest options that may suit the client. Katie has been at the top of my list when working with time constraints for example in 1031 exchanges. In other situations, she is candid enough to state if the file presented may be better suited with another lender due to her product limitations. I can appreciate that she really looks at the best possible outcome for the client. She is easy to work with and updates me regularly without having to chase her. Katie communicates effectively with my clients and I hear that feedback throughout the process. Katie is the best in class.
Sep 11, 2022

Amlesh Jayakumar recommends Pov Oum

We got so lucky that we got to work with Pov! As first time home buyers, there was a lot about the process that was unknown, and a little daunting -- but Pov went above and beyond to help make the process a lot easier, more transparent, and in general a fun one :). We learned a lot about loans, mortgages, interest rates (you name it) thanks to Pov's patience and willingness to educate us about everything. Above all, she was very professional and helped make process of buying our first home a lot smoother. Do yourself a favor and reach out to her :)
Sep 6, 2022

Erin A. recommends Joel Marks

We had a great experience with Joel. He was kind and patient and answered all of our many, many questions. This was our first home purchase and we are so grateful to have had Joel guiding us through the process. We would absolutely work with him again and will definitely recommend him to our friends!
Sep 6, 2022

Adela Picar recommends Katie Perez


It is my pleasure to strongly recommend Katy! I have been working with Katy for 6 or more years and find her to be truly exceptional! Katy is amazing to work with because of her amazing, positive and eagerness to work with people. Always there to meet the needs of her clients and with her "can do" attitude! Call, text, email and she is right there for you! I have been a realtor for 16 years and we need lenders like Katy to always stay on top of our transactions! She is it for me! Love her!
Sep 2, 2022

Leila Khanna recommends Katie Perez

I have been using Katie for decades and she takes so much time explaining all the details. I always feel like I am the only person she is working with. She has experience, dedication and always goes the extra mile for her clients. I highly recommend her.
Aug 30, 2022

Vince Paratore recommends Kathy Derangi

This is easy...I've worked with Kathy in the past and she continues to be my "go-to" for my needs in this field. Creatively solves any issues that surface and professional all along the way.

Our Team

  • Aisling Ferguson

    NMLS #280915 Loan Consultant - San Francisco
    NMLS #280915 / 1850 - CA BRE #01225420 / 01215943

  • Orlando Diaz

    Sr. Loan Advisor - San Francisco - Montgomery St.
    NMLS #238849 / 1850 - CA BRE #01475255 / 01215943

  • Kathy Derangi

    Loan Consultant - San Francisco - Montgomery St.
    NMLS #1151839 / 1850

  • James W. Argo

    Senior Loan Officer - San Francisco - Montgomery St.
    NMLS #257031 / 1850 - CA DRE #00869591 / 01215943

  • Larry Horowitz

    Loan Consultant - San Francisco - Montgomery St.
    NMLS #239001 / 1850 - CA BRE #01003870 / 01215943

  • Ken Dean

    Loan Consultant - San Francisco - Montgomery St.
    NMLS #237940 / 1850 - CA BRE #0902556 / 01215943

  • Pov Oum

    Loan Officer-San Francisco-Montgomery St.
    NMLS # 1226687 / 1850 - APMC CA BRE #01215943

  • Robin Patronik

    Senior Loan Officer - San Francisco - Montgomery St.
    NMLS #241087 / 1850 - CA BRE #01347330 / 01215943

  • Joel Marks

    Loan Advisor (NMLS: #216888/1850)

  • Kevin Casey

    Loan Consultant - San Francisco - Montgomery St.
    NMLS #238192 / 1850 - CA BRE #01178612 / 01215943

  • Allan McAllister

    Loan Consultant - San Francisco - Montgomery St.
    NMLS #280540 / 1850 - CA BRE #01372084 / 01215943

  • Cecelia Tyeskey

    Reverse Mortgage Specialist - San Francisco - Montgomery St
    NMLS #239861 / 1850 - CA BRE #01212004 / 01215943

  • KC Murphy

    Sr. Loan Consultant - San Francisco - Montgomery St.
    NMLS #255492 / 1850 - CA BRE #1007053 / 01215943

  • Mireille Costandi

    Loan Consultant - San Francisco - Montgomery St.
    NMLS #249322 / 1850 - CA BRE #01132350 / 01215943

  • Ming Leong

    Loan Consultant - San Francisco - Montgomery St.
    NMLS # 252471 / 1850 - CA BRE #01369831 / 01215943

  • Risa J. Meyer

    Mortgage Specialist - San Francisco - Montgomery St.
    NMLS #332214 / 1850 - CA BRE #01126851 / 01215943

  • Sheila Wood

    Manager/Loan Consultant - San Francisco - Montgomery St.
    NMLS #253742 / 1850 - CA BRE #00824166 / 01215943

  • Katie Perez

    Loan Officer
    NMLS #633672/1850 - CA DRE #01215943

  • Bob Siefert

    Senior Vice President - San Francisco - Montgomery St.
    NMLS #55105 / 1850 - CA BRE #00921214 / 01215943

  • Amy Lai

    Loan Consultant - San Francisco - Montgomery St.
    NMLS #341535 / 1850 - CA BRE #01795977 / 01215943

  • Mark Wiener

    Loan Officer - San Francisco - Montgomery St.
    NMLS # 246293 / 1850 - APMC CA BRE #01215943