domain name cost

Recently, I plan to buy a bulk domain from a registrar because I think it should cheaper than buy each domain individally.

The cost of domain selled by international registrar is about $7 when purchase at least 10 domain in one time. It's about 280 Baht while a domain registration in Thailand cost ~350 - 400 Baht, about 100 cheaper. But what are the 10 domains I will register?