She is technically responsible for the paid agreement until November, but she is also the individual who posted the deposit... 

If your state has a security deposit cap collecting the year up front is problematic. 

Hello,I'm reading Avery Carl's book "Short-Term Rental Long-Term Wealth" and she mentions setting up a designated business account and making housekeepers fill out a W9 and paying them through direct deposit or an online invoice payment platform.

Will they respect their obligations when they move out or will they stick you with a large bill for unpaid water bills, damages beyond the deposit and extraordinary cleanup expenses?  

They collect rent and you have to chase them for it, and I think they have a ring of deadbeat tenants that go from one house to the other, and pay a security deposit and nothing more

Then you can deposit the money into the LLC.

You meant you deposited it.

For 'smaller' amounts of under $100k many will even do an automated online appraisal and employment check, instant issuance and funding in five or so days. 

You will be out inspection and appraisal costs, but will get your earnest deposit back.  

The vast majority of lawsuits against Landlords are for wrongful eviction, security deposit disputes, and Fair Housing Violations.