If it's 5+ units, all bets are off and you need to seek commercial financing, which can be tough to obtain when you're just starting out.

TOTAL PROJECT/CONSTRUCTION COST $25,000,000LAND COST $ 3,000,000 (CONTRIBUTED BY US)TOTAL EQUITY (INCLUDING LAND) $ 5,000,000CONSTRUCTION LOAN $ 14,000,000MEZZANINE LOAN $ 6,000,000The developer is getting a fee for the project.

How do I go about ensuring that at the time of closing, the total cost of fixing plus my fee for the fixing and coordination gets into escrow and I get pay out at the time of close and my brother only gets the remainder from this sale?

The debate going forward is continue using my own cash (in total control, no interest, can make more competitive offers to acquire properties, higher $ amount returns, no contractor draw requests/inspections to deal with throughout entire project) or turn to a HML who is going to cost me around 10-11% with 2-3 points interest only loan with no pre-payment penalties (much less cash out of pocket, high cash on cash % return, potentially do multiple projects at once). 

As someone who likes to be conservative with projections in all other things I do, I totally understand the conservatism here.

List is $145K for two duplexes and a SFH, which lease for $2125/mo total.

You bet. 

Now, it really depends on the scope of your project because these fees might be really low and insignificant compared to the total cost of the project.

Total reno (between both buildings) is 200k.

I recently hired one for a house project and got his price per square, but when the roof was finished, he billed me for the total number of shingles used not the size of the house.