On a $40 jacket
On Poshmark, the fee is $8 plus $1.04 Ontario HST, so you keep $30.96 and the buyer pays shipping. On eBay with $15 shipping, the total sale is $55, the fees come to about $8.90 including Ontario HST, and you pay about $15 for the label, so you keep about $31.10 after shipping, before packaging. That’s almost the same, so choose on effort and buyers. The calculator above does this for your own figures.
Which is less work?
Poshmark. You don’t have to work out shipping: the label arrives by email. On eBay you choose the service, weigh the parcel and set the price.
Which has more buyers?
eBay, by a long way, and it shows Canadian listings to US buyers too. Poshmark’s buyers are fashion shoppers, which suits clothes well but not much else.