I might need a second iPhone on a different iCloud account.
Are there good ways to keep their contacts in sync?
You can use the same email account that you use for contacts on both devices (eg. Gmail) even with separate Apple Accounts.
muguy, do you mean to sync my concats with a Google account for both iCloud accounts?
Can I do it without involving Google here?
On iPhone, under Settings -> Contacts -> Contacts Account you can add a second iCloud account to your device, that's how you can sync the contacts of two different iCloud accounts.
How to keep contacts of two different iCloud accounts in sync
