Want to make improvements, but tenants schedule makes it hard.

[Eric DeGray]

I recently bought my first rental property. A 2 family home in Springfield MA area, and it came with 5 year tenants that do not plan to move anytime soon. My question is based on my desire to get into the units and begin making cosmetic improvements. The tenants work all kinds of crazy hours and have small children in the house which makes doing any repair work to the units difficult to schedule. They have not complained about the property at all, however I want them to remain happy since they are good tenants. Should I just wait till they complain or should I force them to schedule a time that works for me and my team to get in there? Would I be better off to wait till summertime when they will be more comfortable taking the kids out for the hours that I need to complete the work? Again it is cosmetic work, however I feel I need to stay on top of improvements and minimize my financial impact in the event someone does move out.

Thanks for any advise.