gigabit router with bt infinity and guest wifi

Hi all,

I'm after getting a wifi router that can connect to the bt infinity modem, has at least one gigabit port and also supports some form of guest wifi, i want to keep my networking items sepearte from guests.

I thought of doing this with a smart switch and a access point but this too costly atm.

I'm after the cheapst one aviliable that fulfil's all these criteria closet i've got is the WNR2000v5 but it doesn't have a gigabit ethernet port.

Thanks in advance