Renters rights and violation of renters privacy?

I have been renting my apartment in Kingston, TN since February of 2011. The managers of the complex (Scottish Arms Apt.) specifically stated that NO animals whatsoever were allowed in the complex. My issue? Not only do the managers have a dog that has bit a child in the complex, but they allow many other renters to have animals. Is it lawful for them to pick and choose which tenants are allowed to have animals and which are not? Also, I have walked in my home on serveral occassions where the manager has been standing in my kitchen unannounced with repairmen for the AC unit and while I was at my home, my door was locked he used his key to allow the bug man to come spray my apartment. It was unnannouced and I was unaware of anyone coming in. If I am being wronged by the manager or landlord of an apartment what are my rights? Is it legal for them to just walk in my home without my knowledge? I also have family that lives out of state that is staying with me for the week can the managers tell me that if they are not out by the first of the month I have to be out? Please help. This is the first time I have rented anything and I want to know my rights or at least how to find them.