The money that you end up owing to repay the loan over the 5 year term is now post income tax money unlike how you traditionally are supplying your 401k with pre-tax money.  

To vet guests, you can use a pre-booking form, ask about their plans, and require an ID and signed agreement.

Most community banks in commercial lending will have a pre payment penalty if you refinance or sell. 

Definitely investing a portion into the stock market by either investing it in a dividend portfolio or a pre-tax fund.

There is no additional "risk" on the note like a demand clause etc, but you have  extra expense in upfront one time costs and the pre-payment penalty that most programs are sold with if rates do drop as expected in the future.  

Going forward it would be good to specify that your property management software is the only acceptable method of payment in your lease (if not done so already).It might also be a good idea to check the pre-existing lease to see if they have any clause like that (sounds like you already did that).

There's growing housing desperation to both purchase and sell in markets with pre-existing supply and price constraints. 

I've been pre-approved for a bank loan but haven't thought about someone with experience working with investors for deals.

We are actively managing two fund offerings, one focusing on real property (REO and off market properties), the other focusing on Pre-REO (vacant first mortgages).

I am already have a good lender that has pre-approved me with a DSCR loan so all I need is to find the right market to invest in!