[frobozz]

I was no more frugal having bought a house, than when I was putting all my money away towards a deposit on a house, probably even less so.

I would have thought that the biggest reasons were (roughly) freezing your shelter expense against inflation, and putting an upper limit on how long you pay for shelter.

i.e. If I rent a £1000PCM flat for the rest of my life, my bill for shelter will continue to be roughly £1000PCM in today's money for the rest of my life.

If I buy a house with a £1000PCM mortgage payment, it will remain roughly £1000PCM for the rest the mortgage (though current low interest rates mean that it probably won't), which, in 25 years time could be worth just over half as much as it is now. And in 25 years time, I won't have to spend on shelter any more. I will have maintenance costs to pay for, but they are unlikely to equate more than £1000PCM in today's money over my lifetime.

So, where M is homeowner maintenance costs, someone with N+M living expenses is more likely to be better off than someone with £1000+N living expenses.