I don't see any contractor that can do all those. 3) I never get back the results of the bids nor feedback, I am ok if they go with others, at least give me feedback to improve my bid for the next client by letting me know strengths and weaknesses. 

In my past I hung with those who seen preying on the weak as a means to an end.

Recent sales (last 6 months) is the data you need to determine value.Here there are some neighborhoods that are chronically over valued on the tax assessment.

They are designed to pray on the weak-minded, suggestable person who is casually interested in real estate investing or is really interested, but doesn't want to put the work in to actually achieve anything. 

If it's that weak of a cash flower, even at a 40k discount, it's not not a strong market or asset for rental property investing in this phase of the market.$150 is never going to be enough to cover the incidental stuff that happens outside of your pro-forma expenses.

Overall economic strength or weakness.  

Not countering at all on the initial is a weak move....  

To mitigate this weakness, during the due diligence phase of my recent 3-unit purchase, I walked through with several contractors and listened to what they pointed out.

I am dubious of google related real estate ads - I have done it in the past with very weak results.

Even more of them have weak messaging and mail pieces.