Tenants Breaking Lease After Finding Bed Bugs

[Rebekah Golden]

Hi all, 

My tenants are asking to break their lease after finding bedbugs before they move in. I arranged to have an exterminator come take care of them the day after they were discovered but  they are now asking to break the lease anyway. I have collected first month rent and deposit but am not sure how to handle the situation. Should I refund them anything? I am going to have to find a new tenant which will cost time and money. 

Thanks for any advice!