I got my last kegs when you could still get 4 used for $100. I can't imagine needing more than 14 but if I ever do, I'd probably buy new.
+1. I have over a dozen and I bought a good number of them back then for ~ that price. They all would be considered in good shape today and once a year get taken apart and o-rings all changed, cleared for service. I'm not paying these new prices for used kegs. Honestly, I have enough kegs (for me) not to need to.