In the last 16 months there have been multiple units selling in my building for 175K +.

This isn't a get rich quick game.

Without delay I had this listed with an agent  and we got multiple offers.

I use this one from zillow, and have one spreadsheet per property, if you put multiple properties on it, it will mix some expenses. 

I strongly believe that carefully vetted commercial MF syndication is a good investment vehicle due to many many reasons (professionally managed, more passive, economy of scale due to large units, spread of risk due to multiple partners, and all the goods of Commercial MF like forced appreciation through value add, not only to mention all the tax benefits)...

I’ve completely rehabbed multiple primary residences trading up each time.

Add that to your current 15K, you have a lot of liquid cash to invest multiple properties or a nice MFH in an in demand neighborhood.

If I were in your shoes, I'd probably have a frank and friendly with the tenant and talk a big, threat free game, but point out that her lease does not allow for animals and that she did not disclose the animal to you.

It's very competitive as you're competing with multiple offers and cash offers but you need to go after what you want and start somewhere.

These coaches/mentors will be more invested (they have skin in the game just like the banks will want from you when you borrow) and are a little easier to get a hold of when you need help.