I have 3-year tenants who were PITA at the start. I totally rehabbed the house they live in, and it's one of my nicest houses in Charlotte. Being that the house had previously been vacant many years, and they were my first tenants in the house, I expected some repair calls. But things started to get out of hand. And some issues were being caused by them, like when they'd overload a circuit with several high-draw electronics and such. Even though I'd re-wired the entire house, circuits have their limits.
Anywho... what did I do? I made an appointment to visit and walk the entire property to make note of her concerns. I brought the move-in inspection and photos from our initial walk-through. Some items were things we'd made note of just so she wouldn't be held responsible, but that we wouldn't repair/replace for now (cosmetic stuff). A few items truly were things that I would want fixed, and we made arrangements to fix them. The remaining items... well she was complaining that there were too many leaves in her backyard. 'Dear Tenant, you have several enormous and beautiful trees that I paid a tree expert to carefully limb up and cut back away from the house. You saw those trees and admired them when you were viewing the property. I can do nothing about them." Another is little lizards hanging around the warm sunny brick entryway. She said she's afraid they'll give her a heart attack. [insert the I've-reached-my-limit emoji.] I said, "dear tenant, welcome to NC. We have cute little lizards who love warm sunny bricks. They are 100% harmless. I cannot do anything about them. They're actually helpful because they eat lots of bugs! This is a phobia, and outside of my realm of expertise. She didn't appear too happy about that, but what could I do?
In the end, I laid out what I would and wouldn't do, and I said to her, if you are not happy with that, I would be happy to let you out of your lease, without penalty against your security deposit--I ask only that you give me 60 days notice. I thought for sure she'd go for it, but instead she said, "oh, no, miss Terri! I love my house! I don't want to move." She is otherwise an excellent tenant who takes meticulous care of the property, so I continue to go above and beyond for her a little bit, and I'm happy to do it.
You've gotten a lot of great advice on here already. Maybe my 2 cents helps. I wouldn't use any scare tactics about fumes and such. Maybe do a touch-up with epoxy paint. Definitely address the moisture issue in the bath--this is for the sake of your property, long term. Do whatever you must to install a good exhaust fan, wired to the light switch. Tenants aren't going to open windows to let the moist air out. If she broke the tile, she can either live with it that way or arrange to have it repaired herself, IMHO. Or maybe you can get it done for her later on, at your leisure, but you will charge her. Don't say you'll take it out of the security deposit--get a couple of quotes from tile installers, and show her the estimates. Once she sees what it will cost HER she's likely to back down.
Hope to have been of help.