I listened to the offer, but realized that it can only go up in value. 

As noted by @Sean Brooks your best bet is to have a discussion with the listing agent, state your position with empirical data (recent sales) and hope to get a call in a few months when the seller/agent check in with reality.   

I have been sitting on the sidelines for the past couple years, gathering data, exit strategies, markets, etc, and this website has been a big part of it all.

If your eviction data comes from a third party, then you have to comply with the FCRA.

I started to think about the impact on comparable analysis and how the inaccurate data might artificially increase values in my neighborhood as the price/ square foot was $20 more.

I once did a back of the envelope calculation on long term rates using empirical research and data on the relationship between the fed funds rate and the 10 year treasury.

Median housing price in area is about $150k.I'll be glad to share detailed market data.

In the case where there is a question mark, the data was not found on their website.  

The combined network will remove duplication of listings currently served by both systems, and will now provide information from more than 600 data sources, and distribute approximately three million listings nationwide, or close to 85% of residential listings in the country.Move, Inc.

You find the mortgage amount in the land records or if you do it very large scale you can subscribe to various companies that supply that data.