A family train fare rebooked for about €300 less
He needed a Christmas trip from Prague to Budapest for two adults and two kids. On October 23 he booked RJ 277 on the Austrian rail site for €393.60, on a fare with free cancellation until December 22. Then he had Grok Bot check the Austrian, Hungarian, Czech and RegioJet sites every morning at 9. The Hungarian site showed €70 fares that couldn't actually be booked, and the Czech railway wasn't selling December yet. On October 31 the Czech site opened sales for the same 09:36 train at 2,279 CZK, about €94. He booked it and plans to cancel the first booking for free. He puts the saving at about €300. The trick is the order: book a refundable fare first, then watch for a cheaper one.
Copy this prompt
I've booked [TRAIN OR FLIGHT] on [DATE] for [TRAVELERS] at [PRICE], with free cancellation until [DEADLINE]. Every morning at [TIME], check [LIST OF BOOKING SITES] for the same trip. Only tell me about a fare I can actually book, with the price for all of us, the fare rules and the link. Don't book or cancel anything. Stop checking after [DEADLINE].
Our own prompt, written from what the source describes. We haven't run it ourselves. Text in [BRACKETS] is what you replace.
Watch out for
- Book the cheaper fare before you cancel the first one, and check the cancel deadline.
- Some sites show prices you can't actually buy. Ask the agent to confirm a fare is bookable.
- Cheaper fares may have stricter rules, like no changes or no refund.
Where this comes from
Original post by @LeeMatt17631 on X, Oct 31, 2026. We rewrote it in our own words. The result is what the poster reports.
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