CBSubs to charge a fee to upload a single file?

Can subs be configured to charge a fee for uploading a single file? For instance, an art contest with an entry fee to submit a single work. I would require registration as a free member to site but then charge to upload each individual entry. Maybe combine with docman or remository? But I don't want entrants to have access to any folders, just a blind upload. I need to somehow keep entrants info or username associated with submitted file. Thought about using with JoomGallery, but I also need to accept text and music files. It seems like CB Subs ought to work, but I am not quite sure how, and I want to be sure before I buy.

Any ideas would be greatly appreciated!!

Using CBSubs SQL Actions integration plugin combined with a gallery plugin or a good gallery component.

Example: If your gallery component allows a picture quota per user basis then for example you could set that quota from 0 to 1 when using CBSubs SQL Actions integration to change the database value.

The following is an example only and is by no means an exact usage scenario. This depends entirely on what your gallery component or plugin is capable of!

Component
Categories - Contentest (Limit 1 Per Subscriber)

CBSubs
Merchandise Plan - $10

SQL Actions
UPDATE `#__component` SET `quota` = 1 WHERE `user_id` = [user_id] AND `quota` = 0