Proposals now have the option for your clients to choose the quantities they would like.
To add a quantity option to your proposal template, head to TEMPLATES >> FORMS and edit the proposal you would like. Now in each of the package elements you have the ability to set hard minimum and maximum quantities. Set that how you'd like (it will default 0 - 1000 if not changed). Then you can use the PACKAGE variable drop down to add the quantity box for clients to input that.
I also like the look of side by side! :)
You do not need to have that quantity box in there. If it is not there, it will just default to 1. If you want to allow your clients to choose the amount of items, then do the quantity box.
ON THE CLIENT VIEW:
All they need to do is select the package they want and then edit the quantity if they want more. By selecting, it will default to 1 or whatever minimum quantity that you have set!