Tax implications when paying all-cash for real estate that is under your unmarried partner's name?

When buying real estate, title company usually asks how title should be formed. So had few questions when buying property together (or for) partner with whom you are not married, but have been living together for long time and have common children:

1. If home title would be under "Sole ownership" of partner who is not paying for house, then would this payment be considered as gift against payer’s lifetime gift exemption?

2. Would it still be considered as gift, if title would be under "Joint tenancy", "Tenancy in common" or "Tenants by entirety"? If so, then how would the gift amount be calculated in this case?

3. In Common Law Marriage states like Texas, would it be possible to form property under "Community Property" title? If yes, then would IRS consider this still as a gift that counts towards lifetime gift exemption?

Interested in context of Texas and California.