What was the purpose of the automaton in the scheme of things? Was it to keep Virgil focused on something other than what was playing out with the estate sale and scam, or was it to keep him interested enough in the estate to put up with Claire's erratic behavior until they could sink the hook in him? Maybe it was both? I know it had a lot of symbolism, as well, but I'm trying to look at it from a more practical point of view.
Apart from the symbolism and sending the viewer astray, the automaton parts were crucial for the plan. They send Virgil to Fred, confiding in him and accepting him as his mentor. Without the android Fred wouldn't be involved and without his guidance the group would have little control over Virgil, over giving him the push clearly necessary in order to get 'Claire' - since she couldn't believably go after him.
It also raises the question how Virgil never stops to wonder why these gears magically appear all over the house, sometimes even in the exact same place he had already picked up one before... Later on they even helped him along by having the house keeper give him a lot of the parts. Parts that supposedly were lying around, but the keen observational skills of Virgil have somehow missed. Even though Virgil noticed right away that the first gear had been placed there and must have corroded somewhere else.
"They send Virgil to Fred, confiding in him and accepting him as his mentor." Fred was the caretaker. Did you mean to say Robert, the engineer who put the automaton together and advised Virgil on his relationship with Claire?
Virgil did tell Robert he was curious about the contradictions involved in finding the first gear, as if he knew it was planted there. At that time he didn't know the gears were those of an automaton, though, so that's not what drove him to keep taking the others. However, in the next scene after finding the first gears and taking them to Robert, he's at the auction house evaluating some paintings that had come in. One is called "The Honest" by Umberto Veruda. In the lower right corner of the painting he notices some gears lying on the floor. I haven't been able to figure out the meaning of this scene because if you look online at the real painting, there are no gears. So obviously this was something that was added for effect in the film. Were the gears in the painting what clued him in that the gears may be from an automaton? Maybe that's why he kept gathering them, even though his instincts told him someone was planting them.
Yes, sorry, I meant Robert. He started out by collecting the parts without knowing what they're good for, but I think giving them a purpose of interest to him ensured that he would come back often to Robert.
I do remember the scene you're talking about, though I didn't realize the gears were added and I think I too quickly forgot about them afterwards. I don't quite get how this could have any meaning inside the world depicted (and might just be for the meta level of the viewer). Didn't Robert conclude it to be the automaton anyhow?
I do understand why he kept gathering them and I understand why he wouldn't suspect Robert to have anything to do with it. I don't understand why he doesn't try to find out who lays them out for him. The most likely candidate would be 'Claire' and at a certain point he could have simply asked her. He could have even offered to complete the android (he needed those last parts directly from her anyhow) and give it to her as a present. Would he really choose the android (the 'fake love') over 'Claire'? The other suspect for him would be Fred (yeah, the caretaker, got it now ;)). That guy even suspiciously noticed him picking up the gears and hands him a lot more directly, speeding up the process. It's just that Virgil never even tries to find out who's having him reconstruct the android here, or why - I wouldn't have minded if he tried but never find out in time.
I think the painting was a forgery by the same artist who built the original automaton (I believe Virgil's automaton was built by Billy). An instance of a forger putting a bit of himself into his forgery.