For example, you have a limited time period to identify(then close on) a replacement property.

Good for you for identifying the problem as your own lack of research, that's a mature and correct way to look at things.  

Hopefully we won't repeat 1983 ever again, but being able to identify where we are in that cycle should be apart of every local REI's tool bag.

(b) For each new or current account to supply water, the public and private water suppliers shall maintain a record of identifying information on the applicant for the water service and shall seek reimbursement of unpaid charges for water service furnished initially from the person who incurred the charges.

A full third to your friend for his expertise and the time he will put into identifying properties, viewing them and placing offers, and overseeing/participating in the rehab.

My question is for investors and wholesales: How do you identify RE agents, what are the ideal cash flow zip codes (I'll be living these, to start, so I don't want to live in an area that I'll need to get a pit bull) & what property management companies are the best in the area.

Study up on the different zoning regulations/restrictions for each zone at: http://handbook.dcoz.dc.gov/That should help you better understand the MUs as well as identify which zones will allow 4 units.

Look for someone with a big IRA or someone coming out of a 1031 exchange that needs to identify a property so they don't have to pay taxes on their gains. 

Identify what could go wrong to the extent possible, then plan accordingly.

You can identify the two highest retail price ranges, in greatest demand, per zip code where you can list the rehabbed property.You can use the Realtor to help you find deals and also use Wholesalers.