Can you overbid in Monopoly as a tactic?

Question

So during Monopoly, my sister decided not to buy a property and it was auctioned. My brother had no more than $300 and I had around $700. He kept raising the bid even though he couldn't pay and I didn't know since he wasn't showing his money.

He backed out after he made me raise my bid to $550, despite him only having $300, and I lost a lot more money than I had to because he tricked me. Is that legal? It doesn't explicitly say in the rules that you can't trick players by bidding more than you have but it feels illegal to me.

Answer 1

You may bid more money than you have in cash, but this is very risky because you are obligated to pay it if you win the auction. This may be a reasonable play if you can afford it by mortgaging property and/or selling houses, especially to drive up the price for your opponent. But be careful not to bid more than you can pay after mortgages and sales, as if you win the auction and can't pay your bid, you go bankrupt. In particular, if you bid more than you can afford, you opponents can all just let you win the bid, at which point you go bankrupt and the property you just bought would go up for auction again (in addition to all your other properties).

Whether or not a player is allowed to hide their money is a separate question: Is the amount of money each player has in Monopoly public knowledge?

Source: excerpt of my own answer to a related question

Answer 2

The bigger problem here isn't the auction. It's that your brother didn't have his money in view, so you couldn't even guess how much he had. Tournament rules disallow this, though they don't require the player to disclose the exact amount of cash they have, nor to organize their cash in a way that this is easy to determine.

I could add that technically you would have been able to figure out exactly how much money he had by keeping track of all his transactions, but I don't blame you for not doing this. I certainly would not be able to do it. Still, you can often estimate it; if they mortgaged properly recently or sold a house, you know they're not exactly flush with cash. And if you can see their properties, you can add up their values and get a rough idea of how much the player has spent over the course of the game.

But I think the best solution is to agree to keep all money in view and to allow overbidding. If your opponent tricks you by overbidding when you can see more or less how much money they have, that's on you. Instead, turn the tables and make them pay an enormous debt!

Answer 3

The rules do not say anything about bidding more then you can afford however I think it would be fair to say you can only bid what you can pay. That being said there is also nothing saying you can't sell houses/hotels or mortgage property in order to pay for your winning bid.

In situations like this I think a simple solution would be to require everyone to show how they will pay for their bid when making it. It can either be the needed cash or what will be sold/mortgaged in order to pay for it.

https://www.hasbro.com/common/instruct/monins.pdf

If you do not wish to buy the property, the Banker sells it at auction to the highest bidder. The buyer pays the Bank the amount of the bid in cash and receives the Title Deed card for that property. Any player, including the one who declined the option to buy it at the printed price, may bid. Bidding may start at any price.