09 with yellow/foggy headlights

[hondajt]

My wife's 09 Yaris 5dr is always parked outside and we don't wash/wax like we should and the headlamps are getting less effective. I've just replaced the bulbs with new ones, hoping it was that, but it's definitely the yellow/foggyness on the headlamps.

I've polished my headlamps before on other cars, and no matter what I did, about a year later it always came back, even when regularly applying protectant.

I'm thinking of ordering the LED foglights I've seen here, hoping they would compensate, but I might instead just buy new headlamps from online or something.

What have you done? Any advice for someone without a lot of time free?