I have figured in most of that but I'm not sure how much rehabbing between renters will run because I'm able to do all the work myself.

I'm just starting out and I'm trying to figure out the best way/safest way to structure my investments. 

I have a contingency placed into the rehab figure, as well.

(Bad credit is phone bills to collection and visa often late).The exit strategy is repay the property tax and put on mortgage on an 15 year amort so it will have at roughly 75% LTV in 2 years and refinance with a MIC.My concerns are as followings:If they do not pay I will either lose roughly $20,000 assuming an exit price of $130k or own a property (it's a duplex) that would have roughly IRR of 8% on a 3 year hold in a town that I do want want to own a rental in.The borrowers have enough money to pay as things are now.

There are numerous sites out there you can use to help you to figure this out as well: zillow, trulia, redfin, realtor.com etc. 

You will want to start building a team in the area that you plan to invest, once you have financing figured out you can essentially start to BRRRR (Buy, Rehab, Rent, Refinance, Repeat).Challenges:-Start networking with local investors and you'll learn about what they're doing/how they are finding deals.

If I can figure out how to get private funding or alternative funding of some sort (price is too high for anyone to loan as a SFR), is it a good idea to buy it?

Who's fudging the figures?

If you can say with confidence that the Zestimate is usually within 10% of reality in your market, or is consistently 20% high (or whatever), then it can be a useful rough screening tool for a quick desktop analysis. 

You have to figure out what investment profile works for your situation. $100 monthly profit per door doesn't allow much room for things to go wrong, and they do.