Notice I didn't ask any money back or anything.Lessons learned. 

Recertifications aren't very common any more.

I use gmail and searching for payment amounts or HA ID quickly presents the deposit notice from "Homeaway Payments".

But assuming your property is in Philadelphia, and the squatter does not have a lease, then your only option is Ejectment proceedings thru Common Pleas Court.

@Syrica Brown, if you have a tax certificate you must give written notice to vacate to the owner (do not contact the tenants) and then wait 6 months and then you can file an ejectment lawsuit.

I noticed there haven't been many replies to this thread for quite some time, but figured I'd reply anyway.

We are redoing the floors in the common areas and hallways of a multi-level apartment building.

It's common in short sales for HOA's to pull maneuvers like this unfortunately.

With my job I go over to Jonesboro, AR a good bit and I was looking on Trulia for multifamily properties recently and noticed that there seem to be more options there.

If an end user just put in the listing that lease expires on XX.Talk to tenant and see if he is OK with some limited showings with advance notice and if he will keep place in condition needed to show property.I would consider offering him a cash payment if house sells for top dollar.