Borrowing is a good way to go... My incidence meter does spend much more time sleeping on a shelf than it spends measuring airplanes. Probably everybody knows somebody who's got one and rarely uses it.

They do come up at swap meets for cheap fairly often. I saw one this spring for under $5 and I'm sorry I didn't get it (two would be great for checking wash-in/wash-out and twist between wing panels). They're like building jigs -- most people just never get into using them. (I got great prices for my building jigs at swap meets, too!)