While reading the previous page, it perhaps occurred to you that another house rule might take care of that pesky potential for building shortages: Simply don't limit the number of houses and hotels that can be built to the amount provided with the game.
With this unofficial rule, any agreed-upon token can stand in for a house or hotel after the game's supply has run out. This allows players who were slower to build their monopolies a fair chance to develop those properties and earn more rent on them. However, it also creates an economic bubble similar to those made by the Free Parking jackpot and double salary rules -- except this bubble is made of stainless steel, not bubble gum.
When every player can max out his earning potential, only the players with the very worst dice luck will be in danger of bankruptcy within the first few hours of the game. A shorter game may be a harsher one, but when you get right down to it, the game of Monopoly wasn't meant to be all that fair.
A balance of fortune and strategy is built into the game. If you have more fun playing with these or any other house rules, keep them. Just be aware of how they affect that balance, and don't be afraid to shirk family tradition to make the game more manageable.