Rentredi is a good software but BEWARE if you sign up for automated bill pay, they will charge your account if you do not cancel prior to the renewal and they will not refund your payment even if you request it the same day they pulled the payment from your account. 

I will caution you that if they pull something like this and you immediately start offering any concessions as is repeatedly addressed above - this type of personality will make note of that and the threats will be ongoing for the duration of their tenancy.

Then go pull their booking calendar for the next two months and see what the bookings look like.

I'm unsure if you would be able to combine both loans given that the HELOC is tied to a different property than the one you got traditional financing on.A work around is if you are able to purchase the new property with the HELOC at a significant enough discount, bring the property value up via renovations or additions, then refinance the property, pulling out enough money to repay the HELOC. 

That way, you can get your foot in the door, start building equity, and stay at home a bit longer to save more money.You could also consider the BRRRR method where you buy a fixer-upper, rehab it to add value, rent it out, and then refinance to pull your cash back out.

It’s tough to pull off something similar with $50k-$100k in a short period—it’s just not realistic.

For your second question-either refinance it (you say it is mortgage free, so get a mortgage and pull out that money) or try a home equity line of credit (may not work as it is a rental).The difference in insurance quote with 5% and no coverage is ~ $1200 for the year.

It's important to have a good understanding of the different areas of Cincinnati and Dayton, so you can assure that you're pulling accurate comps.

This reminds me of a police officer  pulling somebody over without reasonable cause and asking to search their vehicle and if the person does not consent, they’re saying you must have something to hide.

No social or credit pull needed upfront.