how to i get my mom to be a rover sitter?

i am 12 and i LOVE dogs but my mom says "we do not have enough money to have a dog" so i found this place "http://Rover.com" and i fell in love! i really want my mom and me to be sitters and board dogs,walk,play with them,potty brakes etc. this way i can still kind of have a dog we have no pets and i really want to sit how do i ask her and convince her? and my dad to.