Use Product Custom Fields
            Use this feature to build Quotes or Invoices with 
structured product or service characteristics that can be filled in 
dynamically. 
            
            When this feature is enabled, the values of Custom fields defined for Products will appear in the Quote/Invoice Description.
            
Example: a Quote for Wall painting, with a Product labelled "Painting". The Product has the Custom fields: Surface of wall, Type of paint. After you add the Product to your Quote,
            tap to Edit the Product and fill in values for the Surface and Type. Click Done to return to the Quote: the values entered for Surface and Type appear in the Quote Product Description.
            Note that the Price is set independently from the Custom field values
            To activate this functionality, check the 'Enable Product Custom Fields' option in the Sales 
Options menu / Quotes tab.