Tips on negotiating first contract rate

[Jabbah]

I'm currently in a permanent role and have been offered a contract in a company where a couple of mates work so it's not through an agency. I know roughly what the contract rate will be but have been warned that the company tries to negotiate down as much as possible. I know what some other people are on, but obviously that is not something that can be discussed or even used as a basis for negotiation, but gives me an idea of what they can offer. Just looking for tips on the best way to negotiate the highest rate from my side.

ETA: Contract negotiation is today at 12...

[Jabbah]

Fairly typical negotiation tactics then I guess.

Contract is apprently IR35 friendly. What kind of take home percentage (after all tax, NI etc) can one expect in that case?

What are the typical total costs to the company for a certain contract rate vs a permanent salary?

If going through an agency what percentage would they get?

[Jabbah]

Thanks guys, all good and got a rate I am happy with