Charging tenant for repairs due to negligence

[Payton L.]

Hello BP! 

   Looking for some advice/feedback. How do you bill clients for repairs due to negligence? For example, we just had to have a plumber come out due to a clogged toilet on one of our properties. The clog was due to a pen and some paper towels, which I made sure to have the plumber document on the invoice. Got everything moving again for $135. In our lease it says that any repairs or maintenance due to negligence will be the tenant's sole expense, so I don't think I will have trouble proving that it is the financial responsibility of the tenant. 

For reference the unit is currently renting for $900 and this tenant is an inherited tenant. This is the first month were collecting rent from them. My initial reaction was to get the bill to the tenant as soon as I receive a copy, but offer to accept payment anytime between now and when rent is due again (the 5th). I feel like this is very reasonable. However, I am very new to REI and being a landlord so I have come here for review from the experts.

TIA!