If you don’t approach this in a business like fashion you will be the one that suffers.

As soon as stainless steel came into fashion I thought they were already outdated things that are going to be dated any day now. 

So, even though I got them to move out in an amiable fashion, I think they could sense that if they didn't, I'd be happy to nail them to the wall LOL.  

Just to add....the security deposit isn't identified as his or hers, so for you to split in any fashion, even if you wanted to, is a recipe for you to be taken into court by one, the other or both. 

They never get back timely fashion, so send a few reminders.

When was the last time you ever had a window break itself in that fashion in your home? 

I don't believe there is such a thing that could possibly replace good old fashioned personal screening. 

Send him a letter on the disposition of the security deposit in a timely fashion according to MA Landlord-tenant law and see what happens.  

Then she will have to contact you in some other fashion for requests.

In those cases, you need a good track record of what a running average (12 months, to account for all seasons) of utilities costs per month, include it in the rent in some fashion, and be sure to occasionally revisit your 12-month running average costs with your provider to ensure you're recapturing those costs.