Prior to the update to Reckon One a few months ago, you only had to input a customer address once when creating a new contact, with the option to add alternative addresses for shipping, business address etc
NOW you have to input the address 3 times in order for the address to display on the invoice.
This change was made due to customer feedback. We were asked for a more definitive invoice to and ship to address structure, as well as the ability to email (invoices, estimates etc..) to different contacts within the business.
You should not need to add an address 3 times as it depends on what address you wish to show. If you just want the invoice to address to show, only complete the postal address.
You can also remove the ship to and / or invoice to address from the invoice template in the settings (see below). Go to Settings > Day to day > Invoices and click on the link to Manage templates > Header
** In a (near) future release we'll add the ability to copy addresses quickly between contact types.