How can I add Cost to a Product which is not a stock item? You can see the column but when you click Edit on each product it is not there., how to make Cost editable?

Hello Rosemary-Jessica, 

Welcome to the Community page,

In regards to the not being able to edit the cost in items that is not stock can we ask what account package you have with us at Quickbooks Online, is it simple start, essentails or plus? 

there is no way to bulk edit the vat, it would be a case of going onto each one and clicking edit and in the vat section selecting the 20%S that you need and ticking the little box where it says inclusive of VAT.