The transvision set at
http://www.earlytelevision.org/transvision_kit.html is probably worth $1500-$2500. Comparible to other rare TVs RCA 621s and Temple 1776s. I think the one in this auction is worth considerable less since it is in pretty bad condition missing the original tuner and with a newer CRT. Worth is very subjective- maybe $300-$800 in the current condition.