Hi @Anthony Van Gilder
I think you need to pick a market, then find an agent and a PM who work with investors. They should help you identify target neighborhoods with specific property characteristics in mind. THEN, you can focus on how to estimate rehab costs and make offers. (I'm right at this stage now). Basically, do what @Dave DeMarinis said.
I have yet to make this process work to fruition, but this is my plan: When you're ready to make offers and you have identified a potential deal, have your agent and/or PM walk the property taking video and then taking pictures (you must train them on how to do this effectively). Review video & pictures, see if the numbers might work including margin. Then, make an offer with an inspection contingency. Then, send an inspector (my PM says it can take a week to get an inspector out there). Refine the rehab estimate. Then, send a SOW to a contractor for a bid (My PM said he'll help with this). Adjust for margin and move forward with the deal if it's still good. Even if you don't get the property, you probably should pay any team member who didn't get paid during this process. Pretty much what @Chris Virgil-Stone said.
This process makes it pretty difficult to get wholesale deals, but that's a price to pay for this investment type.
Repair sheets:
I use this one for my initial estimate (Flip2Freedom - Property Repair Estimate Sheet)
For more detailed estimates and SOW, I use the spreadsheet from "The Book on Estimating Rehab Costs" by J. Scott