You can rent a house too. Obviously the numbers will change, see previous post.
At least where I live it's very tough to rent a nice sized house. Plus in your own house you can customize things, etc. You're not going to invest in a rental to have a fully kosher kitchen.
Sure you will save some money, but many people don't figure on all the added costs of tax, increased utilities, landscaping, insurance, interest, etc.
I rented until we needed more space than an apartment could provide.