Currently, Minnesota has a 13 year payback for a 5kW system and larger systems have quicker payback.  

If I can make it happen, it will increase my equity quicker yielding more possibilities following.

Refinancing into a 30 year mortgage will allow for more monthly cash flow, and allow you to save up quicker for next property!

The strange thing is that the latest one is a smaller investment and quicker turnaround time resulting in a higher ROI, but the interest has been almost nonexistent.Is anyone else noticing this?

I like quicker type transactions to keep the ball rolling but these issues arise all the time.

Depending upon the demand in your smaller market you may be able to unload them quicker.

Do you guys believe house hacking a 3-4 unit apartment as a first time home buyer is a good way to accelerate my income so I can get into the commercial game quicker?

Im not starting from Zero I'm trying to figure out how to add more properties at a quicker pace.

It makes it quicker to analyze if the numbers work. 

They're always quicker, are unsecured so no need to pay title fees, no collateral so no appraisal costs, and can fund in 5-10 business days.Qualifying for this kind of debt is stritly based on personal credit, income, DTI, etc since there's no collateral, but might be a good option for you!