Due to the client requirement initially, I have built 2 OSPF areas (n/ws at different locations) without Area '0' (area 10 & area11). As both locations connect via 'L2L' tunnel, works fine. Inside of the LANS OSPF works fine. Now clent have another location coming up which will have direct P2P link with Area10. So is it recommended to create the new location as Area '0'..?
PS: Client already has legacy OSPF network with area0 and it was predicted earlier that Area10 & 11 will connect to legacy network, but looks like it may not happen in near future.