It depends on labor costs and availability of the various trades in your area, but in LA, retail price to hire a general contractor to do that project would probably be about $250/sqft for the new structure and $100/sqft to remodel the existing structure (down to the studs), plus finishes, fixtures, landscaping and hardscaping.

I use same strategies as @Ryan Murdock. 20% discount on properties is very common but you have to think wholesale and not retail.

I have used him as a "home inspector", but don't expect the detailed written reports like you get in a retail home inspection.  

To do that you need to understand what the retail buyers want/go crazy over.

It's good for determining retail cost of renovation tasks. 

One house is totally worth that much but is on a street with few recent retail sales.

My goal is to focus on the investor niche and not the retail market. 

It's starts at $9.00/mo - QuickBooks for Pro edition which about 90% of my clients are on, I can get for about $180, it retails for $250.

And if you're doing more short term, experimental stuff (mom/pop retail, restaurants, neighborhood services) then if a tenant goes bust you may very well have a long vacancy.

I'll send you my retail leads for you to list and you send me your wholesale leads for me to buy.