Real estate investment is a good example of using other people's money to make money for yourself. The basic principle is to identify a good potential, fix it and rent it out for rental income, and sell it at some point down the road. The key is to identify the good potential properties.
What's good vs. not good all depends on the BAO calculation we did in Sec 7.2 (now you see how easy it is after you did it for the first time). During the house down turn, there are a lot of bank own or short sell opportunities which are good bargins comparing with the good times. Since you are in no hurry to buy the property, you can hold your price firmer and eventually land some good deals.
If you cumulate 3~5 properties for rent, you are doing a fine job in real estate investment. For example, if you work while your wife is at home taking care of the kids, she can manage 3~5 properties without any problem.
When the house market recovers, you can simply sell those properties and hunt for the next opportunities.
OR, if this is your interest, you can really go big on this and make it a living. The key is to do your homework (always calculate your BAO), and be paitient to hunt for the good deal.