I remember pricing kiosks and alternatives for work, for pay-as-you-go internet at a college. Priced both full size standups, sitdowns(like the old tv booths at the airport) and even tabletops(like the megatouchs at the bar) and the cheapest I found was like 1500 for the enclosure, PLUS the cpu. that was the table top. 5-10k seems liek the range that they were for the bigger ones though
Part of the cost has to be making a machine that'll stand that kind of wear n tear, security, and also customized ready to go software