Rat Fink was really pretty easy. I did him some while back (last time the kit was reissued) but I think he is mostly Tamiya acrylics airbrushed on, wiht some outlining done by hand, with a brush, using Tamiya's Transparent Green and Transparent Red. The clear gloss is Tamiya TS series spray paint. It goes on very well and you can build up a nice thick, clear gloss in just a few coats. Put it on thin at first then when you get it pretty shiney, hit it with a good wet coat. The stuff dries pretty fast so you can do the whole thing in a day or two.
Road Agent was Roth's "secret agent" car... it has a pop up back deck with a tape deck gadget inside, opening bubble top, etc. This is only about the third car I had ever built... and its not an easy model to make. Its painted with Tamiya spray paints also.
The models are both shiney but remember also you are looking at them through a glass display case window so there is some reflectivity.