Ok mate here we go, listen to me don't listen to me the choice is yours, there are loads out there but it depends on what you want if you wash regularly use a ph neutral one as it will not strip the glaze,wax and sealent thats assuming you do those, if its a deep clean start from fresh i like autobrite superfoam its thick and very good i also recommend a snow foam lance around £30 to go on pressure washer you can alter the amount of product coming through and the spread you need around 2 inches of product fill the rest of the bottle with fresh warm water auto finesse is very hit and miss in my eyes