Can anyone on the forum, who sells on eBay, explain what charges both eBay & PayPal are currently levying against the checkout price; inc. some explanation of listing fees too, etc.

I just recently had a seller explain that he set his postage at £7 because eBay take 10% of whatever you're stating your postage to be (so 70p in this case); and PayPal would "take 30p" (so whatever that is; 4-5%?) --leaving him with, essentially, £6 to post the item; which he further broke down as £1 for packing materials + £5 for RM first class postage. Aside from whether the last breakdown is justified or not, are these eBay & PayPal charges correct? I mean, are eBay & PayPal not simply taking a percentage cut of the total checkout figure? Were they doing something different previously?

My main points to the seller were:
1) Buyers don't know this, or care --& will simply mark your postage as overpriced when leaving feedback.
2) The more you bump up your postage to compensate for money that eBay & PayPal will take --the more they will take from the postage total.

So unless I'm misunderstanding the complexity of the charges here, would it it not be easier to simply accept the percentage cuts that eBay & PayPal will take (regardless of what pot they take them from), state your postage at cost (for the benefit of the buyer & for your own feedback rating), & simply adjust your starting price (or reserve) to factor in these charges in respect to coming out of the transaction with some cash or profit? Does it really matter, to the seller, what the checkout fees breakdown is (item vs. postage), if eBay & PayPal take percentage cuts from the checkout total? Why artificially overestimate the postage element?

I'm confused...