Yeah either you live in London so are paying at a minimum 1600/month or 20k/year for a 350k mortgage, or if you live in the north or less desirable parts of the south you're gonna be paying 750/month or 9000/year for a 175k mortgage, either way if that's 40%, once you consider tax, bills, heating, food, transport (because no way can you afford to live within walking distance of work as a first time buyer) and whatever else you frankly don't have a whole load left all in
In Canada we’re supposed to be limited to 42% going to housing costs and that’s how they determine how much mortgage they’ll approve. I think most people are hitting that mark if not finding ways of going over.