Review your score and take necessary step to improve it if you are at 650 or below.  

Tenants will push and try to get everything they can from their landlord.Seems you've done everything possible to be reasonable, yet the tenant is not satisified and wants more.As already stated, you are too much of a pushover, so the tenant is seeing how much farther they can push you.Highly advise you to find an experienced residential landlord-tenant attorney ASAP.

Try "stayhikaru reviews."

I remember years ago our attorney reviewing one such issue for a client that was coming over to us. 

.✔ Check BiggerPockets & Google reviews for highly rated PMs.✔ Interview multiple companies – Ask about fees, eviction processes, maintenance handling, and communication.✔ Avoid “set and forget” managers – A good PM should be proactive and transparent with reporting and tenant relations.4.

You are just starting and with no reviews, it will take some time.

Guests provide revenue and guest provide Reviews. 

Has anyone else experienced this kind of mistreatment? 

If communication is an issue, consider getting everything in writing or checking reviews for more feedback.

On buy-and holds we usually replace all the plumbing with pex, no matter what, because galvanized has a life expectation of about 60 years, so I usually take the sooner than later approach.Stick with hard money, like Mach1 or or MKE hard money (Scott Lurie) as they will not leand on a deal that does not pencil out, so you have the added benefit of someone experienced looking over your numbers.