As folks have stated already, cost is a matter of personal perception. We had a member of IPMS/Flight 19 many years ago who would not, under any circumstances, purchase a kit if it retailed for over $20. It didn't matter if it was a kit of his favorite subject, $20 was his line in the sand, and that would usually include the paint he needed for the project, too. Meanwhile, another member would routinely spend at least $100 on any model he built--by the time you totaled up the cost of the kit (and the kits be built were usually at that same $20 point), the aftermarket (and remember, this was the late 1980's--aftermarket was a small sliver of what it is today), the books, the paint, etc., etc., it was close to a C-Note.
And the truth was that both modelers would routinely turn out gorgeous models. The guy who limited himself to $20 would cobble up all sorts of detail from scrap he had lying around the house--and not necessarily plastic scrap. Paper, wood, wire, thread, you name it, he used it--it was all fair game. And the guy who pulled out all the stops was as adept at incorporating all the disparate parts into one gorgeous model. And they both enjoyed themselves while doing it.
To each their own. As I'm fond of saying during my Model Building 101 seminars, the joy of this hobby is that there is no one "right" way to pursue it.