I'm currently under contract with another property and this company has already had me pay for appraisal and is trying to get me to order insurance, but I still haven't received an initial disclosure or anything like it confirming the interest rate and everything. 

Is it worth paying the fees for each stay and getting a long term renter or is it better to keep the reservations? 

I personally would pay to skip the line and condense time. 

The goal would be to refinance after 5 years, use appreciation to pay off 60k, and cash flow would continue to increase over time. 

The payment standard is what Section 8 will pay UP TO, but beware it does not  guarantee they will pay the top amount. 

The guy messaging me says he will be the primary person of contact and be paying with a credit card for payments.

I have to evict a non-paying tenant.

The property comes with one unit occuped and they are paying below market rate.

Look into ways to pay, like special loans, teaming up, or using home equity.

The bank protects you by disbursing payments to the contractor ONLY when certain milestones in the project have been reached.If you're looking to pay for the rehab out of pocket AND want to manage the project yourself, J Scott's books provide a great manual.