What you have would work just fine with a 1mm mini gun. A full sized conventional gun (not HVLP) you could probably manage a coat on a guitar, then you would have to wait while it fills the tank again. With a small compressor, you should stay away from HVLP, they are air hungry (the HV in HVLP refers to the high volume of air they use, the advantage is HVLV guns generate less overspray, so less waste) To clean the gun properly you will need the correct spanners to remove the nozzel, some small tube brushes and the appropriate solvent for what you are spraying. for automotive solvent based paints and clears that's usually general purpose thinners, but there is also special gun cleaner (expensive) solutions. Water based systems use water based solvents for cleaning, usually whatever you use to thin the paint.