ZenCart customization

Please ignore this job offer if you are not okay with my budget. If you want to be invited, you can favourite this job and i will send you an invitation. The website is www.snowycones.com/shop i would like a change in the syrups category. At present to order 12 or more syrups you have to add each flavour from the drop down choice one at a time, I want to be able to choose multiple flavours and numbers of and add to cart with one click. Example is highlight Strawberry x 3 bottles 2 x grape etc. also it must only accept 12 bottles if anyone orders less then they must add more for free shipping, if they order less a charge of £10 will be added. Is this something you can do? I am on a very tight budget but would be bringing in more work if this job goes successful. I would like the work to be completed before 12am UK time tomorrow. My budget is not flexible. Thank you