Your best bet for earning this achievement is to set the game up with six players on one controller. Try to earn the first go by rolling highest. I got second so gave it a whirl and it was fine.
Now every property that is landed on needs to be auctioned off and then make sure your player wins with all other players choosing not to bid. Doing this you can just pay the minimum.
With some luck your player will be ahead of everyone and by buying as many properties as possible you will give yourself the best chance of one of the other 5 players landing on something you own.
I did this on my first attempt using this method. Good luck!