It depends on the price range, how much of a down payment you are making, whether you are willing to keep the property as a rental property after you move out, and many other factors.  However, below is a 2-year, 3-year, 4-year and 5-year analysis of buying versus renting a property valued at $150K compared to $300K, which shows that....

• If you're buying at $150K with a 3.5% down payment, you should be planning to stay in your house for 5+ years.
    
  
• If you're buying at $300K with a 20% down payment, you should be planning to stay in your house for 3+ years.

There are, of course, plenty of extenuating circumstances.  Many people might buy a $150K house (or townhouse) even if they are planning to be there for only 3 years --- because they want their own home (not their landlord's), or to get in a certain neighborhood, or because of the tax benefits (not shown below).

Every buyer's situation is different, and I'd be happy to help you run an analysis similar to those shown below if you're interested in analyzing your best housing move.