They basically want me to find houses that make good investments to they can sell to their investors.I had actually thought about getting my license years ago with the intent to eventually have a property management company; but determined I am not really cut out to have to deal with clients/tenants all day. 

Are you saying no internet access or just no wifi?

@Seth Borman This is the primary estimating stage to determine if it's worth it to walk the property.

I'm offered an investment offering outsized returns (20% preferred return over 90 days), and wondering what I can do or ask to determine whether it's a poor choice of investment.

The deal determines how you will sell it and, if you buy right, you can sell pretty much any deal.You should be attending all your local investor meetings - go to MeetUp.com - to find what investors in your area are looking for, what they buy and where, how they find their properties, etc.Over time you will no doubt wholesale, rehab, hold rentals, etc. all depending upon the property you find as well as your finances at the time.

My question is have you done research to determine the market value of this property. 

During these walkthroughs we determined items that are in disrepair and fixed them. 

@Hai Loc I'm trying to see the build out plans to determine plan B.

If it makes a positive cash flow since day 1 price is not that a price should not be the only determining factor in a long term investment.Are their any leases with the existing tenants or does it have any obligations that you would become obligated for. 

If, at the time of loss, the company determines the ACV of the building is $100,000 your limit needs to be $80,000 or more.