John, it would be best to wash it with a good soap like tide first, then wipe it down with wax and grease remover or pre clean solvent. Don;t use paint thinner. As far a sanding goes get a few red scotch brite pads and scuff it up good. You can fill the chips with body filler or you can buy a good two part catilized putty. The un cat putty shrinks up. Paint is another matter, unless you have a fresh air mask i would stay away from any catilized paint. That really doesn't leave you with much choice. I painted many years and have a lot of health problems because of it. so i know what i am talking about. If you prep it and know that any good paint job is the prep, you can take it to Macco or some shop like that and have them spray it for you. Other wise the material alone will cost you aprox 150. 00 ( been retired for five years so it may be more). Good luck Richard