Quick advice needed: Tenant leaving

[Docelyn L.]

Hi Everyone,

This is my first post but I've been lurking for months. I acquired a property 1.5 month ago. I introduced myself to all 4 tenants and told them I will contact them to get new leases signed. I got 3 of 4 new leases signed with no issue. 

I attempted to meet with tenant #4 unsuccessfully. I caught up with her last Saturday and she set an appointment with me for Sunday Night. She also mentioned issues she was having. I told her I intend to get work on them. She was stressing about a bathroom leak (which she did not report to me). Her son was about to cork it. I told her don't do that, I'll send someone on Monday. It sound like it was a re-occuring issue. I wanted to get to the bottom of it

I called her 30 minutes before our Sunday night appointment to sign the lease. She said she was at work. I tried to reschedule, I didn't get a straight answer.

My plumber went over there on Monday to check the leak issue. She did not let my plumber do any work. She told him she was unhappy with the previous owner and has found a new place. She told the plumber she would call me. 

I did not get a call. I tried calling her twice, I left one voicemail and one text message with no reply. She has not pay March rent. It's officially late today. I need to serve her notice

Her last month rent($500) from the previous owner plus security deposit($300) should be just enough to cover the current amount ($750) of her last month rent. 

Here is my delima: She never told me directly she is leaving. Should I just serve her with late notice, not bring up her moving out, and proceed to file eviction? Or Should I serve her with a letter letting her know my plumber told me she intend to leave and for her to call me to make moving out arrangements?

I want to do the right thing in case I end up in court. But I don't want to spend money/time filing eviction on someone who may be leaving anyway. I'd rather let her know I have no issue with her moving as long as she let me know her plan and stick to it so I can plan accordingly. I don't want her at the apartment beyond the end of the month because that's all her deposit/last month rent covers.

TIA!