Big City is a flexible game that has room for many options not covered in the preceding rules. The following are just a few options players may want to consider to add variety or new challenges to their games. Each should be considered separately, but they can be combined if the players wish.
As a new action, a player may choose to trade one or two cards with other players. The player may trade both cards with a single player or one each with two players. Other players may not trade with each other at this time.
The player announces that he has cards to trade and tells the others what neighborhood or neighborhoods the cards are from. He may also indicate which neighborhoods he is interested in. The player may not mention specific property numbers, however.
The other players may offer a card or cards from the neighborhood requested or from any other neighborhood they wish. They may also not mention specific property numbers. When two players agree to a trade, the players trade the cards to each other face down and then put them into their hands.
If the player cannot arrange for any trades, he may exchange up to two cards with those in the stacks. This is done as in the normal "exchange cards" action, except that the player is limited to a maximum of two cards. If the player was only able to trade one card, he may not exchange the other.
Useless Cards must be Exchanged
Instead of allowing cards made useless by the playing of parks or factories to be discarded, you may want to require they be exchanged for new cards. This makes the effect of the placement even harsher as the affected players must choose between holding the useless cards in their hands or using an entire turn to exchange them for new cards.
It also adds the interesting effect that a player later drawing cards as part of an exchange may draw these useless cards. This adds this as a consideration for players wanting to exchange cards. A single streetcar line
Instead of allowing the streetcar to branch, you may want to limit the placement of streetcars so that you create one continuous, non-branching, non-looping line. When using this variant, players may only add to one end or the other of the line.
They may choose to place both on one end or one each on the two ends. Also, a player may not place a streetcar such that a closed loop is created.
The diagram shows the allowed and disallowed streetcar placements using this variant.
Limited Streetcar Line
Limit building of the streetcar line to inhabited areas of the city. In this variant, a streetcar may be placed only adjacent to a building already in the city. This will make the streetcar bonus and the building of the shopping center much more difficult to achieve.
Limiting Card Drawing
Limit card drawing (either when replacing cards used in building or for exchanges) to those neighborhoods in the city. This will force players to add the new neighborhoods before they can draw cards for them.
Players may want to add new kinds buildings to Big City to give it even more dimension. Hospitals, parking structures, gas stations and restaurants are just a few of the new buildings that come to mind.
Of course, each will have its own building requirements and scoring possibilities. You may create your own folded paper or cardboard models to represent these new buildings or borrow parts from other games to represent them.