How much would a market charge on unlocking a mobile?

[Unbilotitled]

My dad got his Samsung D900 unlocked there about a month ago by the bloke on the market for £5

Im going there this week with my LG Viewty V10B hoping to get it unlocked from tesco to my 02 Simcard

How much do you think this should cost and do you think he will be able to do it, if so how will he unlock it?

Thanks.
+rep

[dirrty]

the max it would be is a tenna. if its anymore, go somewhere else. i think the use a usb cable and some software. not too sure though.