I always rekey all the doors in my rentals when I flip the units for a new tenant as I always worry about the liability of keys floating around. 

What is your practice ? 

What would be a landlords liability if a key from a previous tenant was used to break in and steal? 

Never thought about it, but I would say it’s a good idea.

I've installed smartkey locks on all my rentals and rekey everytime.

I always rekey as well the minute the tenant is out. Tenants that have just moved out tend to keep coming back to check their old mailboxes, so I secure the property as soon as possible. 

I also always re-key all locks.  Not so much because I worry about the previous tenant, but there's no telling who they might have given the key to.  It keeps it "clean".  JIC the new tenant ever has an issue with someone breaking in and appears to have used a key.  I can say unequivocally all the locks had been changed. 

Rekey the minute they're out. It's cheap and easy for me.

We use programmable/electronic locks on our rentals. It’s quick and easy to change code during turnover but they are slightly more expensive than standard key locks.

In some areas, you are required legally to change the locks. I always do for reasons already mentioned.

So glad to read all these posts! 

I rented an older unit from maybe the 1950s and it looks like the locks have never been changed so it got me wondering.....

@Charles East we had a home with a keypad and renter removed and took the back part that holds the batteries. That part isn't sold separately.

That’s interesting and something I had not thought of. Looks like you get to buy a new lock in that situation!

@Mary Mitchell yes, we rekey after every move out, I believe it's the law in IL

I rekey all the locks in between every tenant turnover.  The law in my state doesn't require it, but it's just a good idea.  Even if the previous tenant turns in the keys, you don't know if copies were made or who has a copy.  My lease actually has a section to check off whether or not the locks to the property have or have not been rekeyed, so the new tenant would know.  Plus, I use the Kwikset Smartkey locks so it's quick and free for me to change all the locks, so there's really no reason not to.

One way to save money is to swap lock sets.  

Honestly, with how easy it is to rekey your home these days, I honestly would say it's almost a necessity. I once heard from a friend of mine that another tenant walked into his apartment after his landlord failed to rekey. Came in and the guy was just getting ready to rifle through his belongings-- luckily his tenant was HUGE, so that guy got outta there fast.

Originally posted by @Brian Ploszay :

One way to save money is to swap lock sets.  

 Since it is only $12 to rekey a master/slave lock set i think it is inexpensive insurance. 

I hate the idea of keys floating around. 

@Mary Mitchell I keep using the same locks, same keys. Saves me time and money. I cant even keep track of all the keys so not changing them is one less thing to worry about.

If you rekey the home, are you also changing the code on the garage door and keypad? 

For those of you in bigger cities or crime-ridden neighborhoods, this makes sense. But the truth is, if a former tenant wanted into a former rental, they could break a window just as easy as they could walk in the door. Entering someone's home is a crime and the overwhelming vast majority of  human beings are not criminals so there's little risk of it happening.

In my area, I estimate at least half the residents don't even lock their doors. However, a large percentage also have weapons at the ready and know how to use them. I think that's more of a deterrent to home invasion than a lock change.

@Mary Mitchell

Always because of safety and I can do it easily

Couple minute project for peace of mind

@Mark Fries

That paints a poor image of your character. Integrity and organization/competence, integrity because it's a societal norm to believe the locks have been changed, and competence because having a simple system ie key box is something any middle schooler should be able to do in a half hour with moderate supervision.

If your tenants knew that was the case, what would they do? I question if that's legal.

@Mary Mitchell . Always rekey immediately!

@Mary Mitchell I have a few extra sets of locks and such that I rotate between houses. The lock from a vacancy goes into storage and an “old” one from another place gets installed on the new vacancy. I’d recommend getting one brand of locks and installing them on every new unit you acquire. If you have a lot of units, get a vendor to give you a discount if you only buy locks from them.

I’m currently in the process of replacing the locks on a local Broker’s 75 unit portfolio. All of the doors are going to steel and he’s only have to replace the core of the lock when a unit goes vacant. Plus, the lock-box will fit perfectly on every unit. Sometimes they’re a real pain.

Hope that helps!

@Dan R. It looks like from your profile you are in the military, so I wanna say thanks for your service. Of course I completely disagree with your assessment and I would classify it as extremely opinionated. 40 rental homes, 5 years, 3 evictions and 4 turnovers... This is why I do not believe I need to change out keys or locks. To be honest tenants have no idea what I do with keys or locks. They wanna rent a great home at a great price..that's it. The idea that people are gonna come back and break in is a very very low probability unless you are in an F market.

Stuart from ny state I always rekey I use mrlandlord locks.i can change (rekey) in15 seconds I use a different cylinder- change them the cylinders . I reuse the cylinders in a different property in a later date.