In your example the property is now 3 times the price it was. I dread to think how many times the purchasers salary this now is because sure as hell it will not have increased 3 fold. That's an extra 150k the purchaser has to now find in their life time. And I think I have this right, but you're now stating that to square this out they simply borrow much more money over a longer time? Isn't this the very thing which led to the financial crisis?
The figures are for a fix term of 25 years repayment, its the current interest rates that offsets to some extent the current high (to us) buying price that help with the subsequent affordability.
How can the lenders effectively and accurately predict future interest rates and the recipients longer term future income progression, but this has nearly always been part of the process anyway, the problem for the lender and the recipient is how to mitigate any likely mistakes and perhaps is why current lending criteria seems quite tight.
Accepting my 1990 and 2017 examples are no more than snapshots, if you take them purely as those individual mortgage figures on those two sets of circumstances then £80 000 @ 12% and £230 000 @ 2% on a 25 year repayment mortgage make the repayment amount similar, so if affordability is the critical point when based on those two examples it might suggest that it hasnt changed very much, but I am sure inflation, any wage growth etc might even fall in the £230 000 favour, however its all a bit hypothetical.
Purchase price year 1990: £80 000 @ 12% @ £843.00 per month over 25 years = £252 900 on a property worth after 25 year term + 2 years 2017 £230 000
Todays price 2017: £230 000 @ 2% @ £925.00 per month over 25 years = £277 500 on a property worth after 25 year term in 2042 ??
Of course the key points are that 12%+ didnt hang around forever and we cannot know how long low interest rates will too, but in our own discussion overall it doesnt necessarily show that the current property market is anything particularly unique nor less affordable then it has been at some periods in the past 30+ years, its just different and I am sure it will find a way to assist first time buyers to access it again.