Are you going to store the attachments in the database? It would seem you could set up a page where you uploaded one at a time with one field and could upload as many as you want.
What is the workflow you are hoping for? You can probably get it done by using digital file pro creatively without that feature being added.
Exactly as above
client has 1 to 20 photos
url pointing to upload (attachment) stored in DB
images uploaded to server