I did this with 2 phones and a browser(3 players total).
Use one account to buy the art for the other two accounts which will put half the money in the sellers pocket or get the 3rd account to $0 after a few rounds. Once you hit 0 the ability to get loans appears. Use loans on the other two accounts to get more than $4,000.
Now bid on a piece with the two accounts with over $4,000 until the winning bid is over $4,000. Let someone win and it will pop.