Even if we assume a conservative 5% year over year appreciation on your properties, if leveraged with a 5:1 ratio you should see 25% ROI or IRR with leveraged appreciation alone, not counting "cash flow".

Nothing wrong with being a little conservative and using slightly higher rates

Am I being too conservative at 10%capex 10%repair&maintenance 10%property management and 10%vacancy.

.-  Basement is unfinished but has some existing plumbing, garages, finished walls,  etc. and I conservatively estimate $30,000 to build out each of 2 additional  units

We have not done the background check and don't know what will it report, but he said that he was in a car with three other friends in North Dakota (very conservative state, according to him) and all got caught because they had marijuana pipes.  

The rate is good, but the 15 year amortization is pretty conservative.  

I've come around on the idea of leverage but still very conservative at heart when it comes to racking up too much debt.  

They look at the overall deal to make sure that our margins aren't too tight and that the comps are conservative to account for market fluctuations, going over schedule etc. 

Last week, a property came up for auction that had been vacant for more than three years and needed a complete gut (conservative reno budget of $30K).

Subtracting the $4k in closing for the first purchase, the $2k in closing for the sell a year from now, and the $8.4k in selling fees from a conservative sale value of $140k leaves you with $125,600 minus your purchase price of $118k and you pocket about $8k.