dealer marks on windshield
 

so when the windshield is wet or frosted in the bottom left corner there is a four digit number i assume was written at the dealership.

it was maybe a grease pen? it doesn't show up unless it is wet and it really bothers me.

regular soap won't take it off, any suggestions?

I had very streaky glass all around when my car was new and when conditions were as you described. One of our FR-S guys here in Arizona works for a dealership and after talking to his pdi guy he suggested getting the finest steel wool possible and cleaning the glass with that. I used a Scott scouring pad and cleaned all the glass. I had read on these forums not to use any thing like that on the mirror glass as they would scratch. That might be true as I didn't chance it on the mirrors. My efforts along with several washings and my problem is gone.

Xanax, maybe?

;)

Clay bar the windshield.