As for Carmel, there are actually some reasonable motels there that are basic but clean. You can contact the Chamber Of Commerce for a listing. I have stayed there for about $70 per night just about 2-3 blocks from the main drag. There is a nice little motel on the west end of the main street that is white and it has a large tree grwoing in the courtyard. Last I knew, it was $99\night. Prices may have gone up some since I was there last. I never had a hard time finding parking in Carmel, but you may have to walk 4-5 blocks to the downtown area.
In Carmel, there is the Weston gallery - a must see. There is also Photography West Gallery. Both have a lot of nice work, especially the Weston Gallery. There is no end of shopping, eating and galleries in Carmel.
Monterey used to have the Ansel Adams Gallery, but it closed. The Russ Levin Gallery is there but you may need to call in for an appointment.