#2 would be a little bit of work because you'd have to add fields to the product database for the files, modify the upload and templates to accomidate more uploads and then change the showproduct layouts to handle more images. We'll probably add more to an upgrade in the future.
#3, I'm not sure off the top of my head. You'd have to modify uploadproduct.php to check the timeframe selected and apply a dollar amount to it.
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