[wickedrodent]

Are they like guineas where they need to be introduced carefully to see if they get along or are they just happy to socialise together which ever rats they are with?

They should be introduced carefully, but I believe its rather easy to house them together after they are finally introduced. Unless of course you get a loner-rat. If nothing else you could section off the FN into two parts. Are you going for the 2 level or 3 level?

Also, what sorts of things do they like to play with? Do they play with toys etc? Like cat toys and things?

I have cat jingle balls and loads of places for them to hide. They like hammocks, digging box.. basically anything they can climb in/tunnel through. However, what they like the most is coming out and playing with me.

What sorts of things do they eat? Do they need veggies? What sort of daily diet do they require?

They require a lab block. Harlan or Oxbow- Regal Rat are the best two. I also suggest making a suebees grain mix. I give my rats fruits and veggies once a day (at night) when I give my pigs their 2nd of the day. Lettuce, Pepper, Carrot, and basically a little piece of whatever I have on hand.. The key is moderation. There are only a few things that are forbidden. I think another factor is nothing bigger than their head. A little piece of everything is good.

Here is suebees-- ratsrule.com - suebee's rat diet
Harlan-- Kim's Ark Rat Rescue - Food, Treats and Supplements
Regal rat-- Oxbow Pet Products
More food help-- the Rat Report