We rent single family homes, so we have a conversation about yard maintenance, snow removal etc - have you don't this before, do you have the tools etcI also bring up house cleaning questions, by telling them we had a tenant who did not own a vacuum cleaner, did not know how to run a dishwasher, had a mess in the basement etc - and then see how they respond.That is a non-offensive way to talk about house cleaning and you'd be surprised how different the responses are.

Currently it has this large single-family home that I am running as a STR (https://www.airbnb.com/rooms/1124648152156916536).

Assuming I buy a single-family home in Washington as a primary residence (better chance of being approved than a Multi-family).

These are normally the same investors who are preparing 12 tab excel spread sheets for their $100k BRRRR single family’s…..yeah they’re over compensating. 

I think you should let the tenant go and use this as a lesson to button up processes and fix your lease.

I think it's less likely an owner would use multiple bank accounts for a single property unless they're collecting cash for rents or something like venmo which isn't ideal. 

I was wondering what the process is to get a lot rezoned from a single-family to a multifamily (triplex preferred) in the Temple University area of Pennsylvania.

But you likely aren't going to marry someone after a few text messages and single in person meeting.  

I recently purchased a course on real estate investing and have decided to focus on single-family flips and rentals.

With the goals you've mentioned, as bad as I hate to say it, I'd sell the condo and buy a single family home for you to live in.