Oh boy, I saw the group of astor mech droid builders at C2. As friend of mine told me who plans to buid one said, "These things are like hobby cars. You get the basic the vehicle and start buidling up. Once you think you're finished, you think of upgrades and you sink more money to into that thing. You build the R2, you want to add some of the accessories, now you mant to make him remote-controlled, etc."