There are a number of mortgage calculators online, such as the one provided by SPF, which give a good general idea of how much a mortgage will cost per month, taking into account the price of the property, the deposit available, the length of the mortgage and the rate of interest.
While these are mostly one-off costs, they still need to be considered when deciding whether you can afford a mortgage. They will all be tabled in a mortgage illustration document which your lender should provide.
The terms of the mortgage may also affect your decision: are there missed payment fees or early repayment charges? The latter could be significant if, for example, you’re planning to use part of your pension to pay off your mortgage early. And if you’re getting one of the less common types of mortgage, such as an offset, you will need to consider whether you can afford to devote enough of your savings to make it worthwhile.