I wouldn't even trust the last set of accounts myself - they only report what as been put down on paper - if you get my meaning.
It might be an idea - if you have the time - to go and watch the shop and see for yourself the footfall - at different times, across different days.
Does it rely on a big customer - is there a works or school say, when everybody calls at lunchtime - if so make sure the big customer doesn't suddenly moves away - works closes, school merges with another somewhere else - sort of thing.
What's access like - will you rely on passing trade - if so can people park - yellow lines, waiting times, parking charges, etc.
I'm sure you know all this already.
I think small businesses can claim a business rate rebate from the council - up to £1,000pa I believe.
£6k sounds a bargain - too good to be true perhaps?
Make sure you don't get stuck with a 10 year head lease or something!
Worth checking shop hygeine history with Council's Environmental Health office maybe - don't want to own a shop with a bad local reputation.
Get a celebraty to open the shop - Chorley's top fan and Business Woman of the Year, perhaps?