CF at current rates after all actual and budgeted expenses would be 80K a year for four rentals. 

For example you won't have repairs every month but at some point you'll have a $1k repair and if you've budgeted $100 for monthly repairs you'll be fine.

However, I am entertaining a partnership with a member that has low funds  (2,000) but a stable income.

For the example above the lot was sold for $800K+, which further reduces the budget left for construction (demo existing property, clear the lot, excavate, etc.). 

As others have alluded to, I think it is a good idea get all of your team in place so you can confidently move on properties as they arise with as accurate of budgets as possible.

For your entertainment, the first deal structure600,0005% down 30k, 2k for 36 mths=72k, balloon payment of 540,000 in year 372k=5% 30k towards 10% downpayment with the remaining 42K as financing fee to seller for holding the note for 3yrsyes I know it looks like a drawing with fat crayons by a 2 year old/unfortunately you don't know what you don't know!!

He wants to sell all 3 at the same time, but has said he will entertain offers to buy 1 building a year for 3 years, which is what I offered as that is what I can afford to do.

You don't have an expense for that.Always include a budget for initial repairs.

Now you could buy your investors out or sell it to another entity you own but you would need to disclose, check the operating agreement, and then meet whatever returns you budgeted to the investors. 

We were able to get their offer accepted and the house is going to work for their purposes, it meets their goals, and is under budget, but it certainly was not what they were originally looking for when we started the process.