Try visiting well known auction websites to see how much toys are selling for.
To give you a head start, here are 5 toys that have held, and often increased in, value, since they were first launched on the market decades ago.
1. Pokemon Cards
Worth between £2 - £1,500
Still being traded today, as much as they were in the mid-nineties peak, with some of the rarest cards now changing hands for as much as £1,500. That could be next year's summer holiday sorted!
2. Star Wars Figures
Worth between £15 - £1,000
Even with the latest franchise spawning a new wave of toys, it's the original figurines from the first film in 1977 that are still the most popular, even in a slightly worn, well-loved condition!
3. Hornby Trains
Worth between 99p - £700
Items by the classic British model train company are a great find, and while a simple goods wagon can sell for as little as 99p, other, more rare, pieces can fetch upwards of £500 - wow!
4. Nintendo Game & Watch
Worth between £20 - £600
Pre-dating the iconic Gameboy, Game & Watch was among the first handheld, battery-powered units, and dominated the '80s gaming scene. Used, and even broken, models are being snapped up regularly on eBay.
5. Action Man
Worth between £10 - £600
The classic action figure has stood the test of time, and represents a solid investment for toy collectors. Also track down accessories, like weapons, clothing, and vehicles, as these are popular, too.
Is today the day you pop open the loft and discover a rare toy covered in dust? You could be enjoying an unexpected holiday in the sun or storing away your treasured and valuable toy for the next generation in your family.