Do I have to park domains with Pro Sites?

Hi there,

I am sure this has come up before so please forgive me. I want my users to be able to sign up through pro sites and either purchase their domain or use an existing domain. If they purchase their domain I want it to automatically set the proper configuration so they don't have to do anything. If they choose their own, all i want them to have to do is change the nameservers or A record.

Is there any way around adding it as a parked domain in cPanel? Does a dedicated IP fix this issue? I have a VPS and not shared hosting.

Thanks for the help!