I haven't seen a ton of kits, but the flat roof makes it seem more likely to be scratch; the kits usually add a roof slope.
Check for an isolated wheel set, this might have been on anything from T-rail to Outside 3rd rail as well.
The lettering doesn't look hand painted to me. The serif work, vertical alignment, corners, and line variances in curves is too tight. It would done larger, be photographed, shrunk in developing, and then screen printed or litho printed, on the wood, to a decal or dry transfer etc..Most hobby shops had the truss equipment and couplers (Scale City sells similar couplers from old tooling ???) Trucks didn't always come with the kits either. "No tellin".
A "crude" build? 
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How about "whimsical"? 
Cars like these are what I always loved about old school 2rail layouts. The fact it was "scale" had little influence on my attraction; it's that hand groomed flair of detailing; I see folk art. 
