You will not beat the easy of paypal for 30 a month. its a good starter to see if what you are doing is going to make it. Getting a full blown merchant accout is a pain and tpically lots of otehr fees (paypal is quick and easy to set up). Paypal is flat 30 a month and like 0.30 per transaction and % is based on the sales dollars. I have used them for my mainstream site and it has been great.
Also you can use paypals usps/mailing for free to generate labels. Thats a $15 a month savings right their
1. flat fee 30.00
2. none
3. 0.30 per transaction and 2.9% per sales total to start. I am at 2.2% right now and it automaically lowers once you hit sales goals.
4. thats it see # 3