How to stop abuse? Again!

First, I had people ordering products, choosing to pay via check/mo...and they never do pay. A team of people, probably my competition, messing with my inventory by doing this and creating confusion...every single day of the week. So, this great pay by check/mo feature used by customers, had to be shut off.

But that is not stopping them from setting up new accounts. Now that I stopped them from placing fake orders, these people are setting up new accounts under false names, emails, etc.

There should be an email confimation feature before they can open an account. This way, even if they fake it, they most likely will not have a few hundred email addresses, etc.

Is there any solution to this problem? If there is, boy would I like to learn of it!

Thanks.

I had the same problem before where accounts were being created usually by bots. When I installed CAPTCHA for account creation, it stopped.

How does this change the current user experience?

Customer will need to enter a CAPTCHA when they are creating an account. I think most people are familiar with this now a days especially when they are submitting a form. It has not deterred people on my site from creating an account.