I go through the stacks of plans and stuff once in a while and throw out the garbage that adds up real fast.
And then there are the hundreds of limited edition art prints that haven't sold.... and may never.
The paperwork (book keeping stuff)....thats another matter. In Canada we have to keep it on file for at least 7 years, and anything before that we have to petition to destroy. Usually this is allowed only for a good reason. Like damaged by flood or no longer in business.
So it's all stacked away in a closet taking up space.
But there's more important stuff to worry about I suppose.
-dan
Now for the receipts, invoices, etc. I ain't got any. Decided a while ago to go paperless. Everything gets entered into my accounting software, scanned and burned to a cd. I keep stuff in a file and deal with it when I'm bored (or at end of month so I can see where I am with my projections). The only thing I keep paper copies of (related to accounting) is my income tax returns.
then i do the same thing for income (ie, invoices marked paid). it seems to take a lot longer to fill those envelopes.
the really important stuff is the month-by-month ledgers. those i pay attention to - everything else is just paper in boxes.
all design notes go into file jackets with the customer name on it. before and after photos go here to, if any. the digital design files (the finished work) is archived onto zip disks, stored off-site. these are pretty lean - i have notes on the colors or materials used, sizes and so on. i don't keep the sketches or other ephemera. my rule of thumb is "what would i need to recreate the sign if it were destroyed in an accident and the insurance company would only pay for replacement?"
my sign software now allows me to print out a job summary page with all the info on it - the design (in color), customer info, dimensions, substrate, colors used, date, etc. i'm starting to use these one-page prints as the complete job summary, plus a couple of photos. if i needed to look up the invoice, i've got the date (so i check the envelope with that date range).