Anyone have tips on painting diecast? Is it just like painting a real car, as in body prep,primer etc? Or do i need a special type of surface sealer???

Pretty much. There is an easy (not so good) way and a difficult way. I havetaken steel wool and soap and scuffed the entire surface, then used Ajax and a toothe brush for a finer grit and lastly, softscrub and a toothbrush. This will get you a wet sanded look that you CAN paint over if you are looking for the easy way.

The way I have done it is to strip it with paint stripper, scrub it completely clean to remove all residue, thin coat(s) of primer, a soft scrub once over and final coats.

Others may have different methods, but both of these have worked fine for me.