It's good to get a lifetimes worth of knowledge off somebody in only an hour or so.

Define the value of this property relative to your time you need to sell.Is the market going up, flat, going down and by what percent a month.

From what I understand however, he has made quite a few bad financial decisions in his lifetime.

The numbers seem to work even if I sell the units at the purchase price years down-the-road.The remaining funds will be kept in reserve for about a year in case a surprise develops with the houses/renters.Questions:-are the structures of the deals reasonable (interest rate, timeline, percent down)?

If he can perform and you want to keep working with him (i personally wouldn't), I'd restructure it to be more disassociated, ie maybe let him have the business and consult for him and get a percent share..if you trust that he will pay you. 

Have an interested investor that would do it if I could bring about 20-30 percent ROI.

Sold the flip two months later with 35 percent take on the property.

I am 21 with a savings for 18 percent of the asking price (roughly 209k) and could meet conventional mortgage lending requirementsThanks guys 

Generally the Condo Managers are learnt o give out the info other than for the CQ due the fact how they answer may impact loan approvals for the condo.Initially, if you are buying the condo as an investor (not owner occupied) your loan process will be more stringent and your lender with get the CQ to get the Condo Budget, the HOA delinquency rate (no more than 15% late), Master Insurance, Fidelity Insurance,  percent of units owned by investors, and percent of owners that own more that 1 unit.Determining the ARV in DC shouldn't be too hard because the sales are plentiful at all phases.Once you rehab or you are done with your holding period, you want your unit marketable to all buyers so you want to make sure your Condo is on the FHA & VA approved lists of Condos.  

Bottom line is you can preach 10-12 year holds all you want and your NA investors will nod their heads and swear they're in it for the long term but in five years in they're all going to be wanting their money back.I'm talking to investors from Asia whose investment horizon is fifty years or more and that changes what you're willing to pay significantly.