Can I only sell a few items?

I have a few items around my office that have never been opened and are just collecting dust. These are in good condition and I want to sell them to recoup some of their cost. I’m concerned about shipping costs as I live in Canada and shipping rates can be high.

Can I just sell 5-10 items on Amazon Canada?

I have one item that is pretty heavy (50lbs) that I want to sell but I’m afraid of high shipping costs. Is there any way to sell/ship this without breaking the bank?