Also, this presumes that you know both where and in what type of house you'd like to live in in the future. Both are usually pretty variable as life circumstances change.
True things can change, but he says they know where they want to end up. Some people actually do know what they plan to do in life.
Fair enough, but life has a funny way of throwing curve balls. Family circumstances change, jobs change, attitudes change, finances change, the housing market changes. It would be no fun to end up with two houses you don't want.
The most important question is, does the other house constitute a good investment in its own right? If the numbers work, it could be a reasonable plan. If not, there's no reason to saddle yourself with a dubious investment and the attendant mental and financial pain.
Slight variation of this idea has come up three times in the forum recently. I think rising prices have caused people to start thinking multiple steps ahead. However, buying for fear of getting priced out is usually a poor strategy.
