Tax Write-off for rented room

[Chris C.]

Hi All, I recently rented out a room in my house for 3 months.  What all can I write off?

Also, he ended up not mowing the lawn (which he was supposed to), and the city came out and did it.  I did have my friend mow the front and sides, just not the back, but then city then came and mowed it all im guessing??.  Anyways, i already refunded his deposit, can i use the bill from the city as a write-off?