Their cost basis is about $33k, the agreed upon purchase price is $250K and the expected appraisal might be around $350k-$400k. 

Yes, there's a shortage of low-cost housing in West Palm Beach and Malibu and Portland Oregon and Asheville NC and other places people want to live.

Three Months ago, low to mid 6's were available.Rates are going to continually fluctuate but if you have a way to earn 10+% on your capital, the TIME you are not using it is going to cost you way more than the extra .5% per year will.You are walking over dollars to save pennies if you are waiting for the perfect rate, half of the people who held out on getting mid 6's were waiting for high 5's.

I would avoid working with Leslie Pappas / Archer Investors at all costs.

How much is the rehab going to cost, what's the ARV going to be, and how much will the property rent for?

It cost $38,000 for the framer to take on the risk and do the work - and that does not include the cost of the GC, or architect, or plumber that was also required!)  

I get that labor costs (along with everything else!)

You won't find a deal where you live for free, but if you can live in a great neighborhood at a reduced cost of living that is a nearly risk free way to get started in real estate. 

However what happens when the tenant vacates and now the unit has to be turned over/takes a few months to find a new tenant and during that same period of time the sewer line goes and you get hit with that $15,000 cap ex expense in addition to the vacancy and turn over costs.

Do you have a total price range you're looking for, or maybe a cost/door?