I don't know about #1, maybe someone here does, or you might contact
sales
surpasshosting.com and ask them. I know that if you give Support your old cPanel information they will go in and transfer your whole site for you.
As for #2, nope, you aren't charged to move your domain. You'll just change your nameserves to the ones Surpass gives you and that'll be that. Unless, you don't own your domains and you're transferring the ownership from someone else, then that would be over my head since I've never done that. But I assume you own your domain, so it's probably moot.
#3, you can upgrade whenever you feel. You'll be creditted for the unused portion of your billing, too once your upgrade is finished. If you choose to do so, that is. And nope, there's no fee to upgrade. You just fill out an upgrade form and order the new plan.
Hope I helped! And welcome to Surpass and Surmunity!