Build an Online Store

I'm currently in the process of designing a website with open cart for my new online print store. I need an extension which allows me to, within one product, have different options which all affect the price. Ie. Product = Business Card Turnaround Time = 1 working day or 2-3 working days or 4+working days Weight = 350gsm or 400gsm or 450 gsm Folding Required = No Folding or Half Fold or Z Fold Lamination = Unlaminated or Matt Laminated or Gloss Laminated Number of Sides = Single Sided or Double Sided Quantity = 100 or 250 or 500 or 1000 (etc.) After reading around i've seen that a way of doing this is using excel spreadsheets as csv files, would this be the best way? And would it be possible to get all of this information in one product? A few examples of similar ideas are; [login to view URL]?pt=5&lt=1&ps=81&pat=3&ppn=2&prt=2&ft=3 [login to view URL] [login to view URL] The general idea of this is so that i don't have thousands of products for the customer to look through - which makes it confusing, i want it in a nice, simple one page list ([login to view URL] example) or grid (route 1 example) format within one product. I understand for all the different options it may need both list and grid (again i.e. route 1 example). The successful freelancer should be able to show a good demo of an extension/site they have built showing this or something similar working with a simple back end (i.e. csv files) which makes it easy for me to sort/ change prices as and when needed without changing complicated formulas. In said product I would also need a file upload button (this comes as standard with open cart - the following doesn't) that shows a thumbnail and progress bar. Customer should be able to upload pdf, psd, jpeg, word, publisher, png & psd - allow files up to around 25mb(isn). Thanks Nick NB - In the future i am hoping to add a design feature to the website as a separate product and charge flat fees for the templates and the feature that they can simply add to their cart as a downloadable product. If it would be easier to do this now or you have a template already set up with what I'm already looking for including this - please let me know as i understand it could be easier doing it all in one go (the reason that i haven't included this in my initial brief is because of initial budget restraints) Please contact me if you need any more info or clarification.