: You cannot have more than a one-house difference between properties in a group.

: The bank must have houses available; if they are sold out, you must wait for someone to sell theirs back. The Buying Process

: Look at the Title Deed card for the property to see the cost per house. Pay the Bank : Hand the required cash to the Banker.

: You must own all properties in a color group (e.g., all three reds).

Are you dealing with a in your current game?

: None of the properties in that color group can be mortgaged.

: Once you have four houses on every property in a group, you can "buy" a hotel by returning the four houses and paying the hotel price. If you'd like to dive deeper, let me know:

In Monopoly , you buy houses to increase the rent other players pay when they land on your properties. You can only buy houses during your turn or between the turns of other players, provided you meet specific ownership and building rules. Requirements for Buying Houses