OK made some (small) progress but still getting stuck. I now have this:
SELECT T1.PaymentNumber, T1.TillID, T1.BranchID, T1.TransactionNumber, T1.Payment, T1.CreationDate, T2.SalesNumber, T2.CustomerID, T2.PLU, T2.Description, T2.Retail, T3.FirstName, T3.LastName, T3.Street, T3.District...