Is it more for what you're getting now or will it include extra channels? There are quite a selection of upgrades, we pay £68 and get everything except Sky Sports which is another huge whack on top.
You need to negotiate hard - perhaps threaten to leave ... I was paying just under £37 a month for everything (including all the movies and sport in HD).
I now pay £49 because I've got a main Sky Q box (with UHD TV - which is stunning for Movies and Sport - although not quite enough content yet) and a second mini-box in the bedroom with all the same channels in HD.
I bought a Humax box last year for about £175. I record everything I want to watch and that's it. I watch Freeview and there are more than enough programmes for me to choose from. I wouldn't waste my money on Sky unless there was something I followed - like sport.