Is it a given that you will stay in that location in 10 years?
Homeownership in Canada is really a nasty beast, but this is still a lifestyle question. Is staying in your location worth what it's going to cost to stay there? That's really the question you need to answer.
As for what to spend, our household has made under 150K for the last 4 years and we have no kids, and we could never feel comfortable buying a place over 500K on that income.
Some people could, but for us that would be too tight, we would sooner relocate than commit that much cash flow to housing.
That's just us though, that's our personal lifestyle priorities. But that's kind of my point, you need to seriously hammer out what your priorities are and if living in that location rises to the top of the priority list.
We've purchased 3 properties (4 units) in the last 5 years, with the specific purpose of locking in low housing prices in inexpensive areas before they get too expensive. We have a 1 bedroom condo in a major Ontario city, a larger duplex in a small New Brunswick city, and a small detached home in a tiny Newfoundland village. Total purchase price for all 3 was 388K.
We've lived in each location and there are substantial pros and cons to each, but we did an enormous amount of research and found the areas where factors we could tolerate significantly lowered the cost of housing.
And that's pretty much it. There's a reason real estate where you live is expensive, and you need to figure out if paying a premium for those reasons is worth it or not.
If it is, then it's a matter of looking at your income and determining what other things you can cut that aren't as valuable as owning in that location.
There's really no rule of thumb. The max we're willing to pay for housing on the same income is likely radically different because we have different priorities.
If it were me in your situation, I would rent until I retire and then take all of the extra savings I have and relocate somewhere cheaper when I retire. The shitty part is that if you want to stay in that location indefinitely, then rising housing costs will actually hurt you as your expenses on the house will just go up with higher taxes.
So the question is less about how much you want to spend now, but what do you think you will want from a location in the future, and what that is worth to you now.