Stamps.com = overpriced for the casual user, buyer beware!
My experience. Tried it out as a survey suggestion, as it had a 30-day trial. Unfortunately, I thought it was pay-as-you-go fee structure as the cost wasn't clear on sign-up.
Then I accidentally signed up again when I activated the software. So I was being billed twice before I got my credit card statement. When I thought I had it cleared up (she gave me credit for the other account and canceled it, plus was supposed to upgrade me to the $20 postage - but only moved my existing $5 on each to the original account, totalling $10).
Next statement arrived a few days later and I had been billed twice again for the next month. At $15 each billing, I was already out $60. And no, Stamps.com doesn't refund - unless you go through a supervisor. But they gave me a month's credit and I got them to send me that free scale they had also promised (which is usually jumping through hoops to get, from what I'd heard.
Scale arrived today. It is useless without the proprietary Stamps.com software, which only runs on a PC. Has no readout, just a USB cable. Good thing is that you can use it without having to have an active account. Bad thing is that it isn't worth the $49.95 you pay for it. Checking on ebay showed that it sold for $2.25, with a 25% success rate. Means people don't want and can't use this scale for anything else.
Three thumbs down. Extremely over-priced nonsense along with their habit for over-billing.
You have to save enough to pay off that $15 every month. Unlikely.
Here's how you can pay all your eBay and other shipping needs:
USPS ClickNShip will print labels and pick up priority and express packages for you and send you free supplies (you just pay shipping on the supplies). Their self-adhesive labels are pricey, though.
PayPal will also print Priority and Express labels, as well as First-Class Packages. You can print them on regular paper and tape them onto an oversized envelope (just don't cover the barcode). PayPal makes you pay for confirmation in order to guarantee their products, though. So it's a minimum of about $1.40 per first-class large envelope.
Want to know the weight? Get one of those cheap Pelouze scales. (I got one for just under $15, total with shipping.) Good enough for First Class. Then look up what you'll have to have for extra postage. Turns out the post office sells a wide variety of stamps right on their site - and plenty of 1-cent stamps to make up the slight difference.
Example: My info products ship out on a CD with an insert and come in just under 2 oz. And they are stiff cardboard, which can't be machined - so I need to pay a total of 79 cents per item. Get some 78-cent and 1-cent stamps and I'm in business for cheap. (Someone did send me a CD which had been put through their mechanical sorter, but it looked a bit beat up when arrived - still worked though - and only had a 53-cent stamp on it...)
Or - get one of those Stamps.com scales on eBay and download their latest software, and then don't register for it. Buy your stamps from anyone except Stamps.com and you'll be getting everything done a lot cheaper and faster.
Of course, they'll eventually upgrade and won't support legacy software, so the advice on their scale is time-limited. That Pelouze scale has been around for ages, though...