Thank you for the answer, but it's not possible for my 1st question? the second one? or both?

Do you know if that'll change with v8?

To first question, I guess you would use e-commerce module to sell online and pos module to sell physical, they both should be able to work on same inventory.  To second question I also hope, that might come earlier, I am pretty sure my clients wont be happy to hear, that they have literally no control on what to sell or better, if I someone would buy certain quantity of a product, they would be legally obliged to deliver.