hm, i want to allow my customers to downloan 40 files only
what i mean is i want my customer to purcahse a download card
(same meaning as a gift card, like $20)
so i allow my customer to download 40 different files
(so it's like 50 cents per file)
well, i don't care how long it takes for each customer to use up $20
but i just do not want customer to make payment each time they buy one file

or.... i have to have them pay first....
i do not set # of files they can download
but i just want them to make a payment, say $20 first

awk... do you guys actually get what i mean?