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Sunday 13 May 2018 at 10:13
A better question might be what's the most you've ever lost on a pin. If you buy a 12k pin, play it for a year and sell it for 12k, most people will be really happy about that. It's the 7k Congo after restoration that you sell for 5k that hurts.
The most I lost was $600 on a RFM.
Source: http://pinside.com/pinball/forum/topic/what%e2%80%99s-the-most-expensive-pin-you%e2%80%99ve-ever-purchased/page/2#post-4395326