Dependent Fields for Quote Creation

[KNickolay]

Hello! 

Since we sync our CRM with our ERP, we are in need of a way to set a property requirement before they can create a quote. 

Example use case: if a deal is taxable, they must calculate sales tax prior to the quote getting created (calculating sales tax is within a custom card). Since they update their line items not in a custom card, but rather within the natural HubSpot right-hand property, we need a way to lock down the "create a quote" button until they calculate tax for a taxable deal.