Mandatory fees can reverse a headline-price comparison. Record when the full amount becomes visible and compare offers at the same stage of checkout.
Here are invented event tickets. Seller A advertises $70 then adds a $9 booking fee and $3 service fee. Seller B shows $79 including mandatory charges. A initially looks $9 cheaper. Its final total exceeds B’s by $3.
The FTC’s dark-patterns report includes hidden and late-revealed costs among the practices it examines. Record when the full totals become visible.
Read the values
| Item | Value |
|---|---|
| A: headline | $70 |
| A: final total | $82 |
| B: full price | $79 |
Separate mandatory and optional charges. A seat upgrade can be declined; a required booking fee cannot. Delivery may depend on the chosen method or location, so compare under the conditions you would use.
If a late fee changes the winner, revise the comparison rather than treating the earlier choice as settled. You still pay the higher total even after spending time entering your details. Compare again if the fee changes which seller costs less.
Keep a record of the headline, the added lines and the final total. That shows exactly how the price changed and which costs were disclosed at each step. You can see which fee changed the comparison and when you first had a chance to read it.
Sources
FTC: Bringing Dark Patterns to LightUS staff report, 2022. Examples of interface practices; local rules vary.