Originally Posted by
the_gironian
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Flight prices
This might be one of the trickiest, but still there are some interesting tricks. You can know for sure that a price is not going to go down if you see the "X seats remaining at this price" mark. And you can see the next price if you do a search with more passengers than seats remaining! If you don't see the scary sentence, then the price might get lower during one of their usual promotions.
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My bolding. I'm afraid that's not correct - sometimes Ryanair later go on to offer the flight at a lower price after that message has appeared (e.g. if they're trying to fill up the plane). What they don't do is actually offer a fare at that very same price level - so the sentence is accurate on a literal level.
Skyscanner's Price Alerts email service (prices checked daily) can be useful for tracking price fluctuations, though note it covers all airlines flying a route - but if Ryanair is the only airline flying between two airports then you can use it to get an idea of how their pricing works.