It depends where you are and what your market is like and what type of property you have. Not all things are equal. I'm in the Toronto area and I work in the Greater Toronto Area from Oshawa to Milton. I own a property management company and we do a lot of rentals.
So basically the smaller and cheaper the apartment, the quicker it moves. The people who would rent a one bedroom basement are more likely to be more transient, move more often and move more quickly. For this type of apartment, it's not unusual to find a tenant the week before they move in.
One bedroom condos downtown, same deal, the people are very mobile, couples, young professionals, singles. They live to rent about a week into the month for the end of the month. Quite often, we'll rent these back to back, with no vacancy at all.
Two bedroom condos and townhouses tend to be a little higher priced, and attract people who don't move as often. Townhouses are very attractively priced as a rental and have most of the benefits of a detached house and so attract a very stable family tenant.
Three and 4 bedroom townhouses,more stable working families tend to stay quite a while, also very attractive to divorcing people of higher status that are transitioning.
Then there are some really sweet rental properties, really nice family homes, luxury price point, they take a while to rent, sometimes 2-3 months. People will start looking months ahead to rent these properties, obviously, presentation is an issue.
Wintertime is your enemy. People just aren't moving around holidays. There's not too much you can do about it and price concessions just hurt you in the long run.
This lovely 4 bedroom I've sent the picture of, it's super nice, but it's doubtful that someone qualified will just move right in. It will take a while to market the property and for people to make up their mind.