This calculator gives you an idea as to how much you can expect to borrow, and where such borrowing is generally considered affordable given expected interest rate cycles.
Some people may be able to borrow higher multiples according to their personal circumstances and the market at the time, if they are willing to accept the risks involved.*
*If you are an ordinary employee and you borrow 6x salary, an increase in mortgage rates could leave you penniless and then repossessed. Borrowing at high multiples is normally only suitable for those used to taking very high risks (and willing to accept the potential consequences), or who expect a rapid increase in income.