You're young, you do things yourself...repairs, maintenance, lawn care, snow removal...kinda because physically, you can, and financially, because of the mortgage payment, you can't afford to have it done.You're old, mortgages are gone, but physically, and maybe, mentally, you just can't/don't feel like, doing it anymore.In a way, it's good, it keeps you in the game, or you'd burn out, either physically and/or mentally.I bring this up because we've just had our first snow, and instead of getting in my truck to go and do snow removal at my buildings, I'm on my third cup of coffee, browsing the internet with the knowledge that my snow is taken care of by a hired service.Feels good.Maybe I could winter in Florida...

I graduated with a 4.0 in high school but was not interested in pursuing college and finding a job in corporate America.

Use a pro.I'll bet that most all of those who do their own incorporating made mistakes and failed to really map out the Operating Agreement properly for better operations and corporate protection, most all, with the exception to attorneys and perhaps CPA types.

I'm going to keep D4D but also want to incorporate some other avenues to get the phone ringing. 

Ideally, we would like to avoid needing to go in physically to each bank to save time in the process.3) Credit Impact - I read somewhere that applying many different places for financing, then not using them can impact your credit score.

Yes, it is a bit more of a hassle to have to physically show up, but for me, I feel I will be 10x more successful if I negotiate in-person.

Is it worth incorporating LLC?

There are all kinds of scientific (i.e. physics) reasons why this occurs. 

If you know for certain the property, or at least the physical house, would not see water during a 100 year storm, you could have a survey done as part of the inspection to confirm the elevations throughout the property.  

If their lease has expired and they seem to still have their stuff in the house, then you will need to get a "Writ of Restitution from the court in order to have them (the tenants) be physically removed from your property and legally evicted.