Do you get that a house price rise of 10% doesn't actually mean all house prices have risen at exactly 10%? Round my way smaller houses have risen faster than the larger houses, meaning the gap between the two has lessened because of house price rises.
That might be your experience in your local market but that’s unusual.
Mortgage companies do lend more if you have a bigger deposit. That is a fact.
Who said it wasn’t? I said that you’d still need to borrow more. Here is a simple example.
You buy a house for £200k with a £20k deposit, borrowing £180k. Over 5 years you pay off £10k of capital (interest on repayment mortgages is front loaded). The value increases by 20% to £240k. Your equity is £70k (£240k less the remaining £170k you owe).
The house you would like to move to was £400k five years ago when you bought your £200k house. You now have £70k equity for a deposit. That £400k house now costs £480k: 20% increase in value. You’ll need to borrow £410k to buy it and you start again at the beginning of a new mortgage term.
Even if that bigger house had only gone up 10% it now costs £440k and you need to borrow £370k. Much more, despite a bigger deposit. Who’s going to lend you loads more if your income hasn’t changed?
Of course they're not going to lend 6 x of whatever but the little bit extra they will give is often enough to bridge the gap.
It’s not a little bit extra, though, is it? See the example.
It's no point you saying none of this happens as it obviously does, because it's how we have just bought our next house and how our friends are buying their next houses. Just because it's not your experience doesn't mean it's not anyone elses.
The maths don’t lie. Whilst you are merrily taking on more debt and tying yourselves to longer mortgage terms (shedloads more interest) whilst kidding yourselves that you are ‘moving up the ladder’, you could be saving into a pension.