So...what defines a "Cheap car?" I'm genuinely curious.
Under $19,000 or so these days. Pretty much any subcompact or a base trim compact with manual transmission and no options (except for perhaps PFP). Compacts, base-trim intermediates, and small SUVs tend to be "regular cars" ($19,000-$26,000 or so), with anything above that being "luxury cars" (or near luxury if high $20s-$30s, which sadly tends to get overlooked).
It was actually quite a bit more common in the Barker era to have both showcases be carless, with a boat or trailer being the top prize in the better showcase. A car would usually appear every other show, and it almost never was a cheap car, and a luxury or near-luxury car was offered fairly frequently, around three times a month. Since trailers have all but disappeared, those cheap cars have sort of taken their place. Even with those carless showcases, it still beats those grandfather clocks, organs, heavy stereo systems, amphibious vehicles, and dune buggies. Trips seem to appear more often now in showcases anyway, since a lot of people have that furniture that they wouldn't really need.