We have played with a minimum 1st bid of 1/4 the price of the property (to vary with property value, but to allow for unchallenged bids to be profitable from immediately mortgaging; this puts upward pressure on the 2nd bid, pushing it towards the mortgage price).
Incremental bids are then at least the no-house rent amount (and so also varies with property value).
boardgames.stackexchange.com/users/856/Tetteh
If you're playing for "fun", as I typically do, we set the minimum bid to be face value.
Otherwise, set a minimum increase bid of $5 or $10.
boardgames.stackexchange.com/users/180/warren
Disclaimer:
We've never played with the auctions at home.
What I'm saying comes from experience with auctions in other games.
In my experience most unregulated auctions drag on with people outbidding each other with minimal increases.
The minimum bid usually isn't much of an issue.
If people want the item then the price will quickly rise to a certain level.
I'd suggest to use the "no house" or "one house" rent (or so) as the minimum raise amount for each auction.
That also has the advantage of scaling with the value of the property.
As for a minimum opening bid I'd rather go with the mortage value than the face value.
boardgames.stackexchange.com/users/174/Kempeth
If you want to speed up auctions, have everyone submit one sealed bid (this is known as a first-price sealed-bid auction ).
The property is sold to the highest bidder for the price he bid.
Note - I haven't actually played this rule in Monopoly, but I did buy a real property in this kind of auction as it is the way property is usually sold in Scotland.
boardgames.stackexchange.com/users/2364/Tom77
I have played around with the bidding system in the years since I asked this question.
We now play, and I highly recommend the following simple rule:
The minimum bid increment is 10% of the current bid, round up.
So an example auction of minimum bids would be:
A: $100 B: $110 (+10 = 100*10%)
C: $121 (+11)
A: $134
(+13) C: $148 (+14)
A: $163 (+15) ...
This method is still to slow for my personal preference, but it is simple enough for a group that includes kids to actually use.
boardgames.stackexchange.com/users/299/Lee
Let the auctioneer run the auction.
The Official Rules don't specify an auctioneer, but the least conflict of interest , on average, probably arises from having the player who landed on the property, and declined to buy, be the auctioneer.
Then run the auction as a proper New York auction - the type everyone is familiar with from movies and TV.
It is the auctioneer's responsibility to set a minimum price by asking if anyone will bid $X (any amount made up by the auctioneer).
If there are no takers at that price the minimum bid request is lowered until an opening bid is successfully solicited (essentially a semi-Dutch Auction).
This is commonly done by calling out "Do I hear $X" three times before adjusting the solicitation.
Then the bidding continues until no further bids can be solicited.
After each bid is recognized by the auctioneer, the auctioneer is responsible for soliciting higher bids that are any desired amount above the currently recognized bid.
Bids between the currently recognized amount and the solicited bid amount can only be made once the auctioneer calls out "Going once at $Y. ...
Going twice at $Y. ...
Going thrice at $Y and SOLD for $Y." A valid intervening bid amount is only valid between utterance of the first "Going" and the " SOLD ".
Running the auction as a proper New York Auction allows the auctioneer discretion to run the auction efficiently, so the game is not unduly slowed, without introducing any artificial constraints on the valid bid amounts.
boardgames.stackexchange.com/users/5073/Forget I was ever here
The newest standard edition (post 2008)
rules say: Auctions
If you land on an unowned Street, Railroad,or Utility and you don’t want to buy it, the Bankermust auction it.
The Banker starts the auction by offering thespace to everyone for M$10.
Anyone can increase the bid by as little as M$1(even the Banker and the player who originallylanded on the space).
The highest bidder wins the auction, pays theBank, and takes the Title Deed card.
What if no one wants
it?That
’s fine.
No one pays anything.
boardgames.stackexchange.com/users/30096/Ferdinand Liem
Other questions have asserted that many people don't actually auction properties as instructed in the rules.  Monopoly doesn't specify any rules to control the auction.  I have seen auctions stretch on with many +$1 bids, making the process painfully slow.  Seems to me some combination of  eBay bid increments  and/or Poker raise rules would be appropriate.   What minimum bid increment rule(s) are recommended? Do these rule(s) lead to faster auctions?
Minimum bid rule for Monopoly auctions
boardgames.stackexchange.com
<house-rules><monopoly>
boardgames.stackexchange.com/questions/1978
boardgames.stackexchange.com/users/299/Lee
If playing for fun, set the minimum bid to the face value or the mortgage value.  One suggestion is to have the minimum 1st bid of 1/4 the price of the property. One way is to set the minimum bid to be face value, alternately you can go with the mortgage value. To speed things up you can have sealed bids or you can just sell to the highest bidder. You can also set a minimum bid increment of 10% of the current bid.
One suggestion is to have the minimum 1st bid of 1/4 the price of the property. One way is to set the minimum bid to be face value, alternately you can go with the mortgage value. To speed things up you can have sealed bids or you can just sell to the highest bidder. You can also set a minimum bid increment of 10% of the current bid.