Four Questions from Potential New User

Seriously considering WHMCS but have a few questions that I can't find the answers to.

1) Must WHMCS be installed on the same domain as WHM?

2) Is Namecheap domain and SSL fully integrated, automated and functional without additional coding/scriptiing?

3) Will WHMCS work with Paypal Premier account (I don't have a Pro account)

4) What happened to the 15 day free trial?

Thanks!