giving mine a wash as we speak after the Xmas trip away, mine is called "Boat Wash" brand "Boatcare" from the caravan mob, but reckon any fibreglass wash would do. I get the bug guts off the front with a bit of elbow work. Same as the other guys though, I get the cover back on as quickly as possible, mine is a Coast RV as well. even get a trickle charge from the panel under the cover. pays to keep the sun off em when parked up.
Our Panda is only 14months old but so far still looks like new.
HM