Dog sitter staying the night at property? Concern?

[Zach Adams]

Hi all,

I am currently under contract for a duplex and during the inspection, I had time to talk to the current tenants for a long period of time. One major concern to me was they have a dog sitter come into the property whenever the tenant's boyfriend is on a work trip. It appears that the dog sitter has his own bedroom and he conducts his own freelance recording work in that room. I will be inheriting these tenants and want to know some opinions on how to deal with this. My lease has a clause that states that "Guests are not allowed to spend more than 4 nights a month at the Premises...", but wanted to know if this applied to a dog sitter? If not, I would like to make an addition to the lease to ensure he is not residing in the property. Thanks for any opinions on how to deal with this!