Depends. A serviceable LA46, FP40 or the like can be had for $70 or less. Wood for a sophisticated profile, not that much, or $70 to $80 for a kit. Seems to me an Intermediate or lesser Advanced plane with tank, painted, can be put together for $200 or $225, including engine. I've seen a few Vector 40 ARFs with engine that cost something like $225 to $250 ready to fly. (Not allowing for discounts at swaps or the cut rate price of hand me downs from friends.) The Vector 40 ARFs do well up through Advanced, anywhere BOM is moot. No doubt such a plane could be effective in Expert as well. Bad form to ARF in Expert, though. A laser cut Vector 40 kit can be had for around $100. Quite a bargain. IMHO. Add silkspan and dope, CA, Epoxy. Maybe around $50 or $60. (Dunno exactly these days with the price of dope going up.) I'm sure I can put together a scratch built plane for around $100, without engine or tank. Price depends on quality of finish. How many layers of clear, for instance. As far as the cost of Bawsa. Do we count only the Bawsa we used, or all the Bawsa we bought in order to find the pieces we select to use. I've got a scratch built Magician sitting in a jig right now. Doubt the wood cost more than $30. I think it reasonable to estimate a total cost of $60 for that plane without engine or tank. Monokote on the wings, dope and silkspan on the fues. This including a Tom Morris crank. Cheap. Less than the cost of changing the oil in my Passat. (I use synthetic.) Less than the round trip cost of gas to see my CT relatives, 175 miles away.
CL is a CHEAP hobby, these days, like it has always been. For the price of the ticket to a Broadway show, you can build a plane that'll fly all summer. For the cost of heating my row house for a month in Philadelphia during a clod snap, I can build a sophisticated stunter. (With enough left over for half a PA.)