We Value

cor·ner·stone    /ˈkôrnərˌstōn/

  • 1. A stone that forms the base of a corner of a building, joining two walls.
  • 2. An important quality or feature on which a particular thing depends or is based.

We strive to provide you with THOROUGH, OBJECTIVE, INDEPENDENT and UNBIASED opinion backed by our strong Guam real estate market knowledge, advanced education and commitment to professional ethics and standard. Our products and services will enable you to make sound decisions and maximize return on your real estate investment. “We Value” not only what we do but our commitment to you through our professionalism and timely service.

Meet the Team

Siska S. Hutapea
Founder and President

Founder and President of Cornerstone Valuation Guam, Inc., Siska S. Hutapea has engaged in real estate research, valuation and consulting since 1992 in Jakarta, Indonesia. She holds a Bachelor of Science in Structural Engineering from Trisakti University and Master Degree in Real Estate from University of New South Wales in Sydney. She grew up in the appraisal business and her father was the President of Indonesian  Association of Appraisal Companies. She has made Guam home since May 1999 after successful honeymoon with her husband Edward in Guam in August 1998. They raise five children and enjoy Guam’s beautiful beaches.

Ms. Hutapea has over 20 years of experience in Guam real estate. In April 2012, Ms. Hutapea formed Cornerstone Valuation Guam, Inc., a real estate valuation and advisory services company. We Value is the company motto that not only reflects the service provided, but also the way of interactions to staff, clients, vendors, and the public. The company prides itself in  providing strong knowledge and experience as well as an unbiased and objective approach to real property appraisal and analysis. The company is a trusted source of Guam real estate market statistics.

Ms. Hutapea is keeping up to date with world-class knowledge of real estate
valuation, and the only appraiser in Guam with prestigious triple designations from Appraisal Institute, Royal Institute of Chartered Surveyors and International Right of Way Association. Global knowledge with local expert is her concept on making her company a go-to place and devotes company resources on educating her staff. Although small in size, the company provides continuing education, health insurance, 401(k), and additional insurance for its employees. Read More

Commercial Team

Kimberly Kono
Real Estate Appraiser Trainee - Commercial

Ms. Kono began as a Research Analyst at Cornerstone Valuation Guam, Inc. in 2015 and transitioned to a Real Estate Appraiser Trainee in 2018.  Ms. Kono holds a degree in Business Administration concentrating in Finance and Economics from the University of Guam.

Kevin Oberiano
Certified General Appraiser

Starting as a Research Analyst at Cornerstone Valuation Guam, Inc. since 2019, Mr. Oberiano has now transititioned to a Certified General Appraiser in 2022. He holds a degree in Business Administration with a major in Marketing and a specialization in Golf Management from New Mexico State University. 

Residential Team

Noah Austin
Licensed Residential Real Estate Appraiser

 A Licensed Residential Real Estate Appraiser, Mr. Austin relocated back to the island and rejoined the team in 2016.  He previously served as a Research Analyst for Cornerstone Valuation Guam in 2013-14, prior to moving off-island.

Kyle Mendiola
Real Estate Appraiser Trainee - Residential

Joined as a Research Analyst at Cornerstone Valuation Guam, Inc. since the beginning of 2020 and transitioned to a Real Estate Appraiser Trainee by October 2020. Mr. Mendiola is currently in pursuit to obtain his license to be a Residential Real Estate Appraiser in 2022.

Executive Assistant

Diana Graham
Executive Assistant

An Executive Assistant at Cornerstone Valuation Guam, Inc. since September 2019. Ms. Graham has a degree in Secondary Education from a State University in Philippines.