Let's say mortgage repayment is $3000, and rent only covers $2500. Let's add another $500 in overhead. I'm paying $12k per year. $36k would break me financially, but $12k is a good investment, since at the same time, two things are happening:

1) I am one year closer to owning the home. Yay!

2) Inflation. Rents next year might be lower, but rents in 10 years will be higher.