But there's preschool..Where do you live? Go through the public school district.
You know what I do when my mom watches my son...I run out the door like the wind. Because I am tired and need a break. 4 year olds are heathens, no matter how damn cute and squishy their cheeks are. It doesn't matter if your dad is playing video games. Actually I'm impressed, because sometimes when I post here for FIVE minutes I have a kid hanging off my back or occasionally something gets thrown at my head. Or freaking toys plopped in my coffee. If he can pull off a video game with a 4 year old around, that's skill.
I don't know what you want. When my mom watches my son(like tonight), I hook them up with a few bucks for take out, or buy stuff for ice cream sundaes, etc. I can't do a babysitter, either. My mom won't take $ from me but you don't have to pull her leg to eat some ice cream, and it's something that they both can indulge in. Do something like that? It's not going to break the bank.