“BUYING PROPERTY…Whenever you land on an unowned property you may buy that property from the Bank at its printed price. You receive the Title Deed card showing ownership; place it face up in front of you.
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.”

And that’s not all. There’s of course free parking, the landing on of which should not result in you getting extra cash (artificially inflating the amount of money in the game). Everyone knows that one. Marco Arment has some other house rules that he says makes the game better, as well as this one often missed real rule:

“double rent for properties that are part of a monopoly but have no houses”

Ultimately, everything that makes the game better is about speeding it up (by reducing the amount of outside money coming in and speeding up the rate at which people have to pay each other). I’ve played using some of these new (or, rather, old) rules, and it did go a lot faster and make it more fun. I do, however, enjoy the ability to wheel-and-deal on a variety of things, including mergers of certain assets and free rent. It makes the game longer, but it adds to the strategy. It’s probably one of those things that needs to be established before play starts.