You should see parts prices on 450's. We are fortunate that my husband does all repair work but it's still costly.
My daughter just got a new kx 85. Her army brother actually paid for it. He said her 2015 was to old. Lol
Love 2 strokes. Cheap rebuilds
We always put external hour meters on all bikes. So daddy keeps track of rebuild times
Real Motorcross bikes used mixed gas and could be rebuilt in the garage in one all nighter.