How much cash/travellers cheque is required for travelling to uk as a) work permit holder and b) visit ?

i have been offered a job as an executive chef in uk as a 3 star hotel, i will be travelling soon,is it neccessary to have any basic travellers allowance before flying.|||I wouldn't bother with travellers cheques...cash is best....work out how much you will need to keep you until payday with an extra few pounds for travel etc...|||cash is best... good luck in ur new job