Managing tenants moving in and out

[Maya Jones]

We have a unit with 3 tenants, 2 out of 3 seem they will be moving out in december. The remaining tenant wants to bring her girlfriend and the girlfriend cousins in. So going from 3 to 4 total. 

do I need to ask the tenants that are moving out for an official letter stating when they plan to move out? Since their original lease doesnt expire until april 2026, do I say they are still responsible for paying unless I find a replacement tenant? 

can I limit how many people reside in an apartment? I am in chicago. Can I say I want to keep the number of tenants to 3 as original lease? 

i am planning to have everyone new fill out application and background check.

[Peter Mckernan]

You should get something agreed upon for the tenants living and the remaining rent/security deposit if there is something changing from the existing lease. 

For the amount of people living in the unit/house/etc. you should check with the city/state/local laws for this since that will be your backing to say yes or no. You need to be within a limit that are safe and habitable.