Here are the options.

How to get them out: 1. Cash for keys. If they sign a mutual termination agreement to get out of the lease that is perfectly legal.

1. Holdover for cause: Do apartment inspections regularly and often. Every issue they caused cite them. If the issues are health and safety, labor laws like smoking in the building with contractors, not maintaining fire laws (fire alarms and co2 detectors), two instances of nonpayment in 6 months. Get ready to send out 30 day notices to cure. You need two notices to evict for cause. They cannot argue habitability in a holdover.

Good cause includes the tenant:

Subletting the unit without permission

Having a pet when prohibited

Operating a business out of their apartment

Not living in the unit as their primary residence

Paying rent late

Conducting illegal activity

*harassing or threatening neighbors or building staff

If they are nice people explain the cash for keys situation.

Only the owner would know enough about the tenants to figure out what they have to cure. Look at the lease. If the water bill is really high.. Mine is less than $100, you have a leak. The tenant who didn't tell you that is a bill for them they have to pay and they get a 30 days to cure notice. Etc.

Make sure it really is rent controlled. Make sure it has occupancy permits. Make sure you have done what you are supposed to do before you try to get them out.