"Normalized" It comes down to there being a lot of "options" for cars/trucks, and each type was a separate set of mappings (2-joins), etc... it could have been simpler and more flat, but it was excessively normalized to be "flexible".

Like I said, it was pretty crushing on the database... there were a lot of other expensive calculations that ran per request... pre-calculating, caching, and a few other things got some longevity, bit it was a tangled mess of a beast for what would have been 3-4 collections for a document database (mongodb, rethinkdb, etc).