[8.60]Trade Goods staying after buying new Tank

[SCorpA1]

hmm but i bought a frost robot but had alot of valueable goods wich i forgot to sell i dojnt wanted to sell the robot.
what about a junkyard for tanks? or something similiar, like, if you already have bought a tank and you buy it agai´n, you only have to pay the half of the value? but maybe only for 10min or something like this...