And in answer to the question about becoming mortgage-free relatively early, a lot is due to good fortune.
We went to university before tuition fees were introduced. My husband was a sponsored student, so had no student loan for maintenance at the end of it.
We both have relatively well paid jobs (but not the 6 figure salaries often mentioned on MN), and because we couldn’t conceive until late, I was already well established and quite senior by the time our baby came along. We also therefore didn’t have to fund a period of maternity leave and childcare costs when our salaries were lower.
We were also lucky enough to get on the property ladder before it became unaffordable, and benefited from low interest rates on the mortgage.
The one thing that we did have control over is that we have always lived well within our means. Neither of us are bothered about having new things or indicators of status, so our outgoings are quite a lot lower than most of our contemporaries.
So in a lot of ways, we have completely lucked out in life. However, given the choice between being mortgage-free and childless at 40, and having to pay the mortgage off over its full term and being able to have more than one child, I would choose the latter in a heartbeat. So I guess there are swings and roundabouts.