Storage Unit Eviction

[John Robinson]

Bought a multi-use commercial property in December, with retail, residential and some 11 storage units.  
  Previous owner rented the storage units out with a handshake (no lease whatsoever) and I've inherited a renter that's now 6 months behind and another guy that's 2 months behind.  The rest (that are rented) are all up to date and no problem.   I sent out letters informing everyone of the new ownership, have left voicemail messages letting the deadbeats know I can work with them but NEED to hear from them, even if they can't afford to catch up on rent right now.

  No responses.  Units are only setup with a single lock system (unfortunately) so I can't double-lock them.  I can't even install a 2nd lock option without first cutting their lock.

 Since they have no lease, do I still need to do certified letters, post public notices and sit on my hands while they unload everything in the unit some night, or can I at least cut their locks and install new ones?

  Tried searching the forums and internet with no luck. 

Thanks for your advice in advance,

John