One point the article doesn't stress is that charging money removes a whole slew of problems, chief among them spam and ghost accounts. This frees up a lot of development time, since you don't have to make the system resilient to waves of signups by people you'll never see again, or spend a lot of time on abuse prevention.<p>That's the good part. The bad part is, you then use all that spare development time on getting your payment system working smoothly. Since you are taking someone's money at the very outset, making a decent first impression becomes especially important. I suggest setting up payments so if something goes wrong, the account gets activated anyway, and you settle up later by personal contact with the customer.