Your landlord needs to have a talk with his "Buddy".
In most states tenants have the same right to privacy and security as the landowner, this goes for the landlord as well. Again most states require he give "reasonable" notice prior to entry except in emergencies.
On the other hand, in most states you may not withhold rent except in extrme cases of life safety, and this isn't one of them.
In this state that would be grounds for eviction and court fees at worst or late fees at best.
If the landlord provided serviceable locks when you moved in you have no right to Demand that he "Upgrade" them, nor change them without his permission.
If your landlord is a decent sort, he will most likely cooperate with a reasonable request.
Try that first, and if things don't work out ck with the state for a booklet on Landlord/Tenant rights.
Don't do something that may cost you in the long run, Ck it out first.