What are some long term repairs / upgrades that will need to be done - ie- How is the roof, water heater, is there AC?

Upgrade to Pro, the property analysis tools alone will provide enough value to pay for itself.  

Looks like a lot of work to be done to upgrade the units and get higher quality tenets in them.

Codes have changed and while you think you are simply installing base heat, you may also have to upgrade a ton of other things as well.

So that is what we area doing, after some upgrades. 

I would have to see the address and site with price.If you want to place on here for sale you would need to upgrade to plus or pro membership and put in the marketplace section. 

(Due to the fact that I handle our finaces and his language barrier) with some major upgrades done to the house, we have a little bit of equity in the home and our lender has talked to us about digging into our line of credit.

Their presentations are designed to play on the emotions of sheep, peddling products and upgrades and coaching...all founded on the idea that anyone can do this, you don't need money, financial discipline is not required, etc.If you find a seminar, do yourself a favor and Google the name of the individual, the seminar, or the company.

With this being an older house with lots of little issues/needed upgrades, I worry that renting could be an issue without first making several updates. 

We upgraded the bathroom, kitchen, put down beautiful new wood floors, replaced the entryway door and painted.