If you know for sure which tenant is doing the dumping, send them a lease violation and stipulate it must be cleaned up within 48 hours, and you will be doing an inspectionIf it is not cleaned up, you will have maintenance remove the debris and the tenant will be charged for their time and disposal fees.If you are NOT positive which tenant it is, send a letter to all tenants reminding them that common areas are to be kept clear of trash, boxes, bicycles or any personal property. 

I have never heard of a stipulation that says what side the finished side has to be on. 

Any agency debt (Fannie or Freddie) will have an acceleration clause that stipulates any transfer of ownership will make the full mortgage due immediately.  

Stipulate that they will lose their deposit, pay for any needed repairs to have the property rent ready.

In the agreement they sent over there is a clause that stipulates that they receive a 4% commission if I was to sell the property to tenants they place.

People can also be removed for other extreme circumstances such as being violent or breaking the law. if you decide to buy a purely investment property and want it vacant, try offering the seller a little extra and stipulating that he give cash for keys and deliver the property vacant.There are still options in this market.

Their current rental agreements stipulate storage is only allowed in their designated storage units but that obviously hasn't been enforced. 

Now instead of having to choose 'NO Refunds" I have a more flexible cancellation policy that allows me to keep a cancellation fee (which none of their policies other than "NO Refunds" allowed.)Still another benefit of using the Airbnb/VRBO channel manager is that you can stipulate a "rate adjustment" for a particular channel if you wish.

EX: a 12 mth lease stipulates they remain for the duration of the signed lease.

The tenant is correct in NJ it's 30 days written notice unless the local ordinance stipulates something else.