I did my IR a couple of years ago so for prices I am out of date. I think it was £250/hr Duchess and £75/hr sim. You can also wanggle some free sim time on your own if you smile nicely!!
Driving down for the sim would work well, but don't do it for the flying as you will be too exhasuted.
Saturdays did not seem to be a problem for using the sim. They were not too happy about flying at the weekend though, but would at a push (eg. just before a test).
The school buildings are naff, being in an old nissian hut, but the aircraft are tidy and the IR Instructors good.
WWW, me and a bloke from my flying club went there with no snags.
Go and see them if your interested and tell them what you want to do. They are used to holiday time limited individuals like you and me!
It all pays off in the end as I am starting flying a turbo prop at the end of the month. No more worries of squashing in IR renewals in holiday time. Yipppee!!