How do those powersellers on ebay do it?

I’ve checked some power-sellers and their average sales.

One guy who sells cables does on average 302 despatches per week. 

He makes £31500

Minus his eBay fees, listing fees, returns + missing items and final evaluation fees.

Let’s say he makes £25,000.   For that he’s got to deal with 302 listings, 302 sales and 302 feedback.  Plus deal with all the lost items in the mail. 

He’ll have to do his taxation and accounts – that will eat quite a lot of time with this many sales. 

Then he’ll pay an accountant – prob.at least £1000 because of the volume.

He’ll need space for his goods – even if he uses a room in his house, he could have rented that room for £250 per month or £3000.  But let’s say for arguments sake it’s worth £1000 for the inconvience.

So he makes £23000 pre-tax, then pays tax and is left with 15000 profit.  And he’s spending min.40 hours a week servicing all his clients and shipping 2 quid items.

 How do they do it????  Even if they got the goods for 10p it would be hard to make any serious profit.