The kickers are "end cost" and "full set."

I believe the answers will radically differ if the definition of "end cost" goes beyond just money. If end cost includes useful life, the energy required by carry weight, convenience of more compact design, reliability in rough weather, reliability in all seasons, ability to be repaired / sharpened to like-new condition, servicability / ease-of-use, safety features, etcetera, over a lifetime, then the math might include in "end cost" many things more than initial cost.

So, to oversimplify things, I think you need to decide on your acquisition approach based on your best guess of how much camping you are going to do. For those thinking lifetime, slowly accumulating gear toward the high end may represent the best long-term cost strategy. For those reluctantly going on what they hope is a once-in-a-lifetime good weather campout in a local park, borrow / improvise what you can, check out rentals, and then head to the thrift / dollar stores for the rest. If you are in-between or undecided, I suggest keeping things minimal and do the improvise / borrow / rent thing.

In the same vein, one person's "full set" may be overkill or foolish lack of preparedness for: another geographical / ecological location; to support purposes beyond mere camping [hunting, mountain climbing, winter exploration of backwoods, mountain bike touring, trail running, family outdoor weekends, etcetera; and that does not include the propensity for the market to create / reveal camping demands we did not know we had!

Trying to figure out and assemble the "full set" is a great exercise in preparedness planning. Consider letting survival functionality give you at least a start. Look at what you need to avoid violating the Rule of Threes [3 minutes without air, 3 hours without shelter, 3 days without water, 3 weeks without food, and, some say, 3 months without human contact]. Devise your own list of what-I-do-not-want-to-be-without categories [maybe: First Aid, Shelter, Fire, Water, Food, Navigation, Light, Signaling, Self-protection, Hygiene, and Morale].

For this thread, I think first specifying a list of gear would bring everyone onto the same page.