My accountant likes it as I can send him a copy of my file and get his direct input where needed.It also lets me track each asset individually and track WIP for each property so I can get accurate profit and loss statements as I go. 

And so here is my question: is a 60/40 profit split in favor of the sponsor within the range of reasonable "market" splits and where does it fall on the scale?

And when you sell this one after 24 months all the profit will be tax free instead of having to pay ordinary income tax plus self employment on the sale.  

What options do I have in pursuing payment from them?

Generally after everything, mortgage vacancies repairs taxes etc, what net profit should be expected per door?

@Jason DiClemente originally, the main goal was to get our original investment, re-invested profits and any additional cash out so we could continue to buy.

It sounds like you have a great plan and pursue the opportunity :) Help your uncle, the sweat equity to help yourself and keep the house in the family. 

Lucky for you, the greater Puget Sound market is only getting hotter as Seattle prices people out of the city, so if you sell now you'll likely make a pretty good profit.

Research the local limitations or restrictions and pursue both avenues.Good luck!

You say the market’s hot, what about considering:1 taking the bank’s option to Convert to a 30 year fixed term, with maybe piti of $500/ monthly (See if they will lend you 75% of the appraised value OR use the purchase price Plus a detailed list of your costs and repairs) , and then2 selling on contract or lease option at full market price+, ie $119,000 possibly on terms.Look for 10% or more down and finance them as long as your loan is for.This would recoup your initial investment, $12,000+ and costs plus profits And give you passive income of what $200-250+ net monthly?