I got over letting my artwork go very early on. It makes space for new works, so storage is never a problem for me. Plus it also means my artwork is getting out there in the world.
I gave up on scanning my artwork a few years ago. Just too expensive and time costly. I do what Peter does and shoot the artwork with a good lens and lighting. The results are great and I can have it done in no time. You can photograph larger artworks in multiple pieces and then use photo stitching software to put it all together. I've done this a number of times with excellent results.