Pick a customer, add tags, edit the lines, drag to reorder. Three update containers - the lines, the totals, and the live preview (it could all be one container, but this also shows off multi-container updates). One observe field watches the whole form and refreshes all three on change.
| Product | Qty | Unit price | Amount |
|---|---|---|---|
| Widget | 2 | 500 | 1000 |
| Gadget | 1 | 1200 | 1200 |
| Sprocket | 4 | 75 | 300 |
| Total | 2500 | ||