I use a second hard drive on my main tower, so everything can be backed up to more than one location. Another alternative is to plug one of those little USB flash drives into your pc and have it permanently there as an extra drive. That way if your main drive gets corrupted, you are still in business.
The problem with storing things like the actual shop building files on the server Jo Ann, is that you give hackers an easy opportunity to change the 'pay to' parameters of your shop, as well as giving them an easy route to other mischief. Hackers take great joy in maliciously destroying other people's online enterprises, given half the opportunity.