It's becoming very common to use electronic payment.

Electronic communication is legal notice now pretty much everywhere, and it can be text or email, etc.So, something like this:Dear Tenant:It is unfortunate that you have stopped communicating with me regarding your move-out.  

I will probably go with the new cell number, and consider the electronic banking option as a requirement.  

Even a text from them saying they have vacated should be fine for legal notice, as electronic communications are accepted in most states now.If their phone is still working, they should respond when they see you can keep charging them rent.

is there any electronic platform like pay pal that she can use.

I have one door and my primary residence that I rent out the upstairs.In my rental over the last year I have had the following issues/calls:In the first week (when I think you will get the most calls from tenants):Toilet seat was wobbly (It was-very easy fix)Toilet seat wasn't flushing (plastic trip device broke. $10 fix)After that I had 2 calls over the course of the year:The AC unit wasn't draining properly and was leaking out into the house.

We used HelloSign to get the lease signed electronically.  

im looking to have my tenant sign her lease electronically, does anyone have any experience completing a eLease.

I went the free and easy way for electronic rent payments.

If they pay you electronically then if they log in at 12:01 am on the 4th to pay it it's late, if they pay it at 11:59 pm on the 3rd it's not.