You need four of everything and a true LAN isn't possible - all the machines need to be connected to the internet and, short of unique PSN accounts which only have each other as friends, there's no way of stopping external machines joining your room.
Which is exactly what we did for the UKGTP14 LAN, only with ten of everything.
@ fAMINE.
If i go through community and then coffee cup to set up my online lounge would i be correct in assuming only people on my friends list can enter the lobby and race.
Not since the most recent update - only friends of the person who created, or currently owns, the room in a Private lobby may join.
For UKGTP14 we set up LAN-specific accounts. No-one but the other LAN attendees was on the friends list of the accounts. It meant populating them with cars, but a bit of B-Spec Remote Racing and a gifting chain meant we got all 40 cars in all twelve accounts (that's 480 cars) in under two months including the PSN hack and outage.