If you're guided by purely the cheapest way to store large quantities of cigars, then the coolidor is the way to go.
If you put some weight on style and attractiveness for storing at least some of your cigars, especially when offering a cigar to someone, then you need to spend a bit extra on a humidor. It's like offering a fine cognac to someone in a Dixie cup (or even for yourself). Somehow it detracts from the pleasure

My Savoy is stylish, sits in my living room and has been rock-solid in holding humidity. Plus it didn't cost an arm and a leg. Beyond a certain point, the cost of "better" (read more-expensive) humidors is not in their ability to function, but in higher end features like finer woodworking joinery, better woods, extra drawers or shelves, etc. Just like a coolidor will maintain humidity. You just need to decide on what you want.