If I'm reading this right, you estimate the remaining work at $125k, so you're all in at $329k on a house that's worth $280-$320k after it's finished. 

About 20% of the deal came from private money lenders, and the remaining amount came from utilizing my own funds, as well as credit cards to pay contractors & purchase supplies.

We obtained bank financing on this for 80% of the construction costs & brought the remaining downpayment from personal funds.

Our current plan is to split the down payment, secure traditional financing through the use of co-signers, and rent out the remaining bedrooms to other roommates who will pay us a fixed rent amount, and we will use that money to pay the operating expenses of the home.

I am wondering if any lenders can do 75% finance, I put 5-10% down and remainings by sellers finance.

Anyway the remaining question that I have now is - if the lease does not state the EXCLUSION of the garage, but only OMITS it, does that mean they get to use the garage or not?

In all of those cases the tax payer remains the same because the tax return reporting the properties stays the same.That not only simplifies ownership but also lending as well.

They had to cut approximately 25 feet of concrete to tie the new lines into the existing sewer and it was less than $5,000.

Of the 25,000 units my team insures, we don't have a single Pollution policy tied to any of those units.2)  Professional Liability starts around $1000 per year and can cover you for Discrimination and Fair Housing claims. 

Long story short they had some debt tied to the property, we were able to pay that off for them, plus a small extra for them.