To my knowledge the bidder/buyer doesn't see those fees separately.
They'll know what your handling fee is either when they see the postage you paid to mail to them, or they may be like me..I figure out the postage, if it's not on the box.
Talking about handling fees, is like talking about when to leave feedback. It's personal and up to each person. For myself, I judge who's item I'll bid on, when I see the shipping. If I think they start at a low fee, and try to make it up in their shipping (and of course saving themselves eBay fees as well), I pass. I'm not dumb, and I know when someone charges $6.00 to ship something that costs them $1.50 (with the cost of the envelope), they are trying to get people to bid on what appears to be a leeser price than the next guys (a lot of people never look at the shipping, which, of course is their own fault), they are still making a profit, and they aren't going to have to pay fees on it. They are trying to get you to bid on something that appears to be less than the next guys, who may only be charging what it costs (postage and supplies) to ship. I feel like they are trying to "trick" me. I'm not talking about the person selling a 10 # fragile item charging for packing supplies...those are usually legit. But even there, it's up to the bidders to take note and decide if they should bid or not. If the shipping/handling is shown in the auction, bidders should take that into consideration. I would never give a neg for too much shipping, if I was too dumb to agree to pay it. I consider that my own fault.
I charge a handling fee, only on the items I sell all the time (and that fee is usually about .50..sometimes it works out to more, sometimes I take a small hit in the cost, depending on where I'm shipping. I put all my overpays in a jar, and I use that for my self insuring as well. I like to charge a flat fee, so I picked the middle of the country..sometimes it works out good, a few times it doesn't. The overpays pay for the underpays, to the tune of that .50. I don't charge on the items I am trying to get rid of around the house. I don't have to charge a shipping fee for those items, since I get the packing materials free for those items. We do our own packing, and I consider my cost for that, to be what I got for the item.
So to sum it all up, if you have to pay for your shipping supplies (although I hope you are looking around for inexpensive supplies), gas money to the post office, someone to pack, then you should charge for them..do I think you should be expected to get all of your Paypal and eBay fees as well, in the handling? I don't, but that's the part that's personal, and I'll make my judgement call, when I decide to bid or not to bid on your items : ) I get a lot of comments on my great packing, and judging by my return buyers, my s/h is working out just right for me.
Doris