A crony is getting to grips with mail-merge to send letters for the museum he runs, and has worked out that this is the way to prepare a couple of hundred letters with identical text and different addresses.

So far so good, but his printer isn't up it: so he'd like to create a single .pdf containing all the letters and then go to a copy-shop. Is this possible? and if so, is there anything in particular he needs to be aware of?

Thanks for any hints and tips!