Hi,
1. As written in the HikaShop product page ; it is a one time payment because you won't have any limitation of time.
With HikaShop Business, you will have a license for one year. That license gave you updates, support and cron task for one year.
Afterwards you can extend your license ; but it won't affect HikaShop (except that you won't receive updates for new features).
2. The license is for one single website ; but for sure the test/development/preproduction websites are fully authorized.
Regards,
Jerome - Obsidev.com
HikaMarket & HikaSerial developer / HikaShop core dev team.
Also helping the HikaShop support team when having some time or couldn't sleep.
By the way, do not send me private message, use the "contact us" form instead.