Well after looking for a pattern for the upgrade costs, I cant figure out a true formula. It seems right around 67% increase rounded to the nearest 100 or 1000 depending on a whim. Also seems like they didnt do it to all of them. The lvl 2 Oil Derrick UG cost sticks out at $6,680.. I think $6,700 should have been the number. Same with the lvl 2 Storage Silo and lvl 2-5 of the Supply Depot.
Actually aside from the few exceptions above everything else seems to end in a '00' buildings, extras, units..
As for the UG times.. I guess they just threw a dart at the wall.