Question 3. Whats to stop someone like a competitor from creating a gazillion listings?

This is a very valid concern and we, as experienced eBay sellers ourselves, understand that competition on eBay can be brutal. To combat this situation, we've incorporated a simple to use yet very effective spam prevention filter which allows you to set limitations to the amount of listings that can be generated. You can limit the amount of listings that can be generated per hour, day, week, and month. This can either apply to the same IP address (person/computer) or a global limit which limits everyone together. You can also apply these limits to certain individual products or all of them. This allows you to select which products may be at greater risk of abuse and give them their own set of spam prevention settings.