Started acting weird a while ago. Getting weirder.

Wipers travel very slowly. When shut off the pass side wiper stays about
1" higher than it is supposed to and sort of shudders as if the wiper
motor is still on. Pressing the single wipe button briefly will lower
the wipers that extra inch and stop the shuddering.

It used to behave like this only on very cold days in winter. But once
the car warmed up it was fine.
This spring the wipers would be in slow mode when just washing the
windsheild but if a hard rain came down they would start working fine. I
thought maybe something just dries out and needs to be wet a bit.
Wishful naive thinking.

But it seems to be getting worse.

I guess I'm looking at a new motor for the wiper system, eh?

How much is that likely to coast me?