About five years ago i was asked to do the congregation audit and in the past way before that have been the Secretary and before that the Accounts bod.
In our hall, besides what went in the box at the back about a dozen folk had a monthly standing order so that tax on their donations could be reclaimed as per jean-luc picard's post above.
Their monthly amount ranged from £10 per month up to about £100 per month. The vast majority were in the £20 - £25 per month range.
The cash from the box amounted to low £100's and so about £600/£700 went to hall upkeep but only about £100/£200 went on literature although this must be dropping acutely.
Then there would be special drives for decorating or repairs and thousands would pour in. We never struggled financially but didn't seem to be awash with so much dough that we could send large sums off to "Mother".
Occasional bequests came through - usually in the low thousands but in our circuit I heard that an old brother owned an old Rolls-Royce (serviceable runner worth about £10K) and he left it to the congregation to be sold in his will for their benefit.