First would be, that depending on the stuff you are selling, you are likely to get a better response from Craigslist or Kijiji.
For many things, the shipping cost will outweigh the value, so any kind of local transaction would be preferred. The standard "will combine shipping" can be an ebay-offered incentive for people who want more than one of your things.
Smaller high-value items would of course be the exception to the previous rule. There the broad reach of eBay might well bring you a better price. Standard consumer electronics, however, would likely not fit into this category, as they change so quickly.
Depending on the amount of stuff you have, two other ideas come to mind. There are likely local flea markets that charge just a few bucks for tables to sell whatever you like. And don't forget the garage sale; a favourite weekend pastime for many in Canada :-)