Real estate deals are all about solving problems and creating positive outcomes for both parties: here you have the opportunity to possible secure an interest-only note with minimum (to no) principal repayment while providing the vendor with an opportunity to reduce their taxes.With respect to mortgage, I'll offer a contrary position to @Nathan Emmert as we make extensive use of variable rate notes/mortgages.  

I keep on receiving "extensions" from the loan company, but I'm starting to feel like there's nothing really they can do on their end, and have to wait for me to refinance the loans. 

For the past couple of months, I’ve been doing extensive research from listening to podcast, to reading and surfing the web.

All need windows, siding, and I'm sure other extensive issues.

Nothing extensive... basically just recreate the initial conversation that you had with him.This will give you leverage in your area with the verification that you aren't a scam artist and use the PD as positioning, which you could then turn into a press release, or mention to every prospect you talk to. 

Make sure the note has a an agreeable extension option to prevent putting yourself in a bad position if things take longer than anticipated.

Whatever you do, screen extensively.  

Have you ever heard of there being some kind of extension or grace period when dealing with current tenants?

just getting the water to shed away from the house would go a long way. you might get some of those corrugated downspout extensions to help get the water away.

The modification of a mortgage/note & DOT is a NEW extension of credit, just as if you are creating a new loan, that modification must then comply with applicable laws, lump sums can be predatory lending.If a significant amount of your income is derived from dealing in notes, you may not be seen as an "investor" but rather, being in the business, much of this is determined from IRS Code and your active participation.