With Chris's kind indulgence, here's what's actually in one of the kits.
(This was purchased at an absurdly reasonable price from that well-known auction site---one of the uncounted 'later' releases with generic markings---and mine came with no box. No biggie.) Scale was probably 'variable' for different entries in the series...I've seen it 'officially' given as anything between HO (1/87) and 1/100...though a quick calculation for this kit (a 40' bus 3.25 inches long) gives roughly 1/148 scale.
The goodies:
'Mighty Van' decals? For a Scenicruiser---one of the most aesthetically-beautiful wheeled creations ever to roll on our great nation's far-flung highways?? I think not....
The quite-unexpected vac-formed 'road' display base---a nice touch.
The hardware: screws for assembly, actual weights included (for use on 'Hot Wheels' tracks, maybe?), and separate tires.
Surprisingly well-detailed chassis, complete set of clear parts, chrome wheels...and (correct) separate-level driver's section of the interior.
And last, but certainly not least, the nicely-detailed exterior and the single-piece main interior level: all in 'worth-the-price-of-admission' lime-green metal flake styrene. (God...I hope it's styrene....)
All-in-all, quite an impressive value for a 'cheapo' kit. I haven't seen any of the others in person, but if they're all this well turned out, it's a great shame they aren't better remembered.
As I mentioned above, I intend to do mine as a Greyhound---the sole original operator. I've seen various rather unimpressive AM decals for the purpose offered on Evil-bay over the years, but I should be able to do a more accurate and complete set on my own, to print on the PC.
That's assuming paint will actually cover that wicked lime-green plastic....