I keep hammering home the idea of getting a digital camera out and snapping hi-resolution photos of the documents, which gives you the ability to keep copies on  your computer for future reference, while offering them free to the client. 

I also mention to my clients, that their alternative can be to get them ordered online directly from the records office at whatever cost the county charges.

It is their option, but if they don't want the doc images up-front in a FREE digital format, they often approach me later for copies at which time I tend to charge a fee for the service of going back and getting the copies, just for the sheer added hassle, outlay in time and out-of-pocket expense, and impact on other project in progress.