when im going homefrom work, right when i get in and turn on the car, the windows start to fog. there was frost on em the other day, my back quarter windwos are useless to look through cuz they are fogged, any help? ive thought about putting a dehumidifier to try and remove the moisture inside, would that help?

If the cars wet inside I would start by drying that. Otherwise switch you HVAC systen to recirculate instead of fresh air.

I think they make some kind of de-fogger spray stuff you can use.

I use "Mer All Clear Anti-fog De-Mister" its not easy to apply without getting streaks on the window but it does work. Apply a few thin coats for best results, and obviously make sure that the window is clean before you apply it.

If the cars wet inside I would start by drying that. Otherwise switch you HVAC systen to recirculate instead of fresh air.
No, you want fresh air, not the recirc option. Also, if you have AC, kick the AC on, and the dryer will blow dry air.

defrost automatically cycles the a/c system