What should I tell potential employers if I'm interviewing for jobs in Ontario but outside my city?

Re willingness to relocate. This is a roadblock in almost every application. I plan on relocating to whatever city the employer is in and often have a few listing ready to look at if I get a positive response back, but they always hesitate a bit that I'm out of their city even if it already says so on my application. I end up getting a rejection and a few of them stated the location issue. I feel like I'm doing something wrong on my end.

And what would be a realistic time to move into a new city? Actually moving is not gonna be an issue for me at all. I mean as in how long does the renting process actually take? I've moved before but across countries and had family i could stay with so it helped a lot. But I haven't moved within Canada before so I'm not familiar with the process and duration...