I've no professional accounting background, but once was an Embassy accountant. But there was a software programme/accounting system we used but that was foreign office specific, and it did most of the work (though it was a right bastard to learn). I just had to make sure it added up properly, and nobody was fiddling their expenses/all expenses properly incurred/justified etc. If it's only money in from members, and as few payments as you mention, and as long as there is somebody to countersign or verify expenditure is justified /oversee/double check payments, so that I wouldn't have sole responsibility, I'd be happy to help out any I can.
I know there is a sort of money manager programme on microsoft somewhere - there was on the old xp as far as I remember. I never used it, but from what you say, there shouldn't be too much bother.
Just as long as you don't expect an accountant's end of year report running into umpteen pages.
mick