If you’re looking to buy one of this year’s most wanted toys for Christmas, you need to act quickly. Prices have been changing rapidly since the annual Dream Toys list was announced on Wednesday, and experts say that the next fortnight is the time to snap up a bargain.

For example, both Boots and Argos are offering three toys for the price of two this week and right now, armed with a bit of insider knowledge, you can pay the big online retailers like Toys R Us, Smyths and Amazon between 4% and 12% less than the prices they advertise to everyone else.

Here are the best deals currently available from the major toy retailers, plus our top tips on how to pay less at the till for toys:

Bop-It! Beats by Hasbro features music by ‘your favourite artists’ including Pound the Alarm by Nicki Minaj, and Levels by Avicii (teenagers not included). Photograph: Hasbro

Bop It! Beats, RRP £21.99 (ages eight and up)

This electronic music game, which can be played alone or with friends, requires super-fast reactions. Over the past 24 hours, prices have fallen dramatically to almost 50% off the RRP, with Toys R Us and Smyths currently battling it out at £11.99. Cheapest online at Smyths, where it will cost you £14.98 including postage.

Disney Frozen Snow Glow Elsa, RRP £34.99 (ages three and up)

This doll of Elsa from the Disney film, Frozen, has a magical snowflake necklace which lights up and plays the song Let It Go when you touch it. Stock levels are already extremely low across the UK and most retailers are already sold out online. Argos, Smyths, The Entertainer, Asda and Toys R Us are all selling it for £34.99, but check whether it’s available at your local store before you travel to save a wasted journey. It is in stock via Amazon and on Wednesday you could buy it there for just £28.99 including delivery – but the price has now shot up to £49.99. Keep checking for prices closer to the RRP as many retailers are expecting new stock deliveries in the coming weeks. Alternatively, you can order it from Toys R Us in the USA for £45 including international delivery (but remember to factor in extra delivery time) or buy a different singing Elsa for £25 from the Disney store.

Disney’s Frozen characters Elsa and Kristoff. Photograph: Mattel

Disney Frozen Sparkle Dolls, RRP £16.99 (recommended for ages three and up)

These assorted dolls, also from the movie Frozen (Anna, Elsa and Kristoff), have elaborate removable clothes and accessories. Again, stock levels are running low. Again, Toys R Us offers the lowest retail prices, as it is selling each for £12.39 (including Kristoff, who typically commands a higher price), but if you take advantage of promotions at Argos or Boots, you can get all three for £34, bringing the cost down to £11.33 per doll. Online, you can buy Elsa from Smyths for £15.39 including delivery.

The Kidizoom Smart Watch. Photograph: VTech Electronics

Kidizoom Smart Watch Vtech, RRP £39.99 (ages five and up)

This digital watch has a touch screen, a built-in camera and a stopwatch, and is available in pink, white or blue. Pick it up in-store at Smyths or Toys R Us for £23.99 – online, order from Smyths for £26.98. A rechargeable battery is included, along with a USB cable.

Little Live Pets Bird and Cage, RRP £19.99 (ages five and up)

The interactive bird inside the cage will respond to your child’s touch by singing, chirping and tweeting. The more it is played with, the “happier” it becomes. Buy it in-store from Toys R Us or Smyths for £14.59 or order online from Smyths for £17.58. The two AAA batteries required are included.

Assorted Minecraft figures. Photograph: Character Options

Minecraft Figures, RRP £7.99 (ages six and up)

There are a wide range of these 8cm action figures from the popular Minecraft video game to collect. Smyths is the cheapest in-store, at £6.99 per figure, or you can buy three for £15.98 from Argos before Tuesday. Online, Amazon is the cheapest again, with prices starting at £6.99, plus £1.49 for delivery.

My Friend Cayla is the world’s first ‘live’ interactive doll. Photograph: Vivid Toy Group

My Friend Cayla, RRP £58.99 (ages three and up)

Ask this doll any question and she’ll answer it … or she will once you’ve managed to sync her to the internet, using an Android or IOS device and a Bluetooth connection. There are “bad words” and pre-defined topics she won’t talk about, and she also plays games, tells stories and discusses photos. Amazon and Toys R Us are the cheapest retailers at £43.79 including delivery. However, Smyths is close behind at £43.99, and you can reduce this price by £6 (to £37.99) when you buy online with code NOV6OFF. The three AA batteries required are not included.

The Nerf Demolisher 2-in-1. Photograph: Hasbro

Nerf Demolisher 2-in-1, RRP £44.99 (ages eight and up)

This “2-in-1” blaster fires darts, missiles or, if you really mean business, both, reportedly up to 27 metres. It allows motorised blasting and the manufacturer warns users not to aim it at the eyes or faces of their enemies. Smyths and Toys R US are the cheapest in-store at £20.99, while Amazon is cheapest online at £20.99 including delivery. The four AA batteries required are not included.

The Lego Movie: Benny’s Spaceship, RRP £79.99 (ages nine and up)

Help Benny construct a spaceship out of Lego, then use the control room to open the cockpit, shoot lasers and fire missiles in a bid to evade the Robo Police. It’s cheapest online and in-store at Smyths or Toys R Us for £53.99 (£47.99 with code NOV6OFF at Smyths).

Toot-Toot Animals Safari Park, RRP £39.99 (one to five years)

This interactive zoo play set has a “magical” track that recognises and responds to each animal that moves along it with phrases, melodies and nature sounds. It’s cheapest in-store at Toys R Us for £28.99 or buy it online at Amazon for £21.79 including delivery.

The Transformers Stomp & Chomp Grimlock. Photograph: Hasbro

Transformers Stomp & Chomp Grimlock, RRP £89.99 (ages four and up)

This 50cm Transformer figure is a scary robot with a sword that changes with one step into a dinosaur with a chomping jaw and light-up eyes. It’s cheapest at Amazon, where it’s currently £47.99. At Smyths and Toys R Us you can buy it for £53.99, including free delivery when ordering online. Two AAA ‘demo’ batteries are included.

Zoomer Dino Boomer, RRP £99.99 (ages five and up)

This robotic dinosaur can chase, chomp, guard and roar. It’s cheapest in store and online at Toys R Us and Smyths, where you can buy it for £47.99 (including delivery). The three AAA batteries required are not included.

How will prices change in the run up to Christmas?

“Right now, prices are as keen as they are going to be,” says Gary Grant, the founder of The Entertainer toy shop. “The next fortnight is the most price-sensitive time for any toy retailer and you will find far more competitive prices in the market now than you will in late November or in December.”

By then, the focus is on availability, he says. “When items are short, there is absolutely no reason to be discounting items that are highly sought after, and so the number of tactical promotions on toys tends to decrease.”

He adds:”The nearer we get to Christmas, the more items will go out of stock. With the Frozen film toys, for example, demand is already extremely high and the market is short.”

John Baulch, the publisher of Toy World Magazine, agrees: “The best deals are to be had right now and there will be shortages closer to Christmas. It’s not a cynical thing – the majority of toy retailers have to make their final call on stock in July or August, and it takes eight weeks for toys to arrive from manufacturers in the far east. Disney’s Frozen toys are popular around the world right now, and the factory has a maximum physical capacity.”

Don’t expect to be able to shop at a single retailer and find the lowest prices for all toys in the run-up to Christmas, Baulch adds: “Supermarkets can make their money on other categories so they will use toys as a loss leader to pull in customers. Meanwhile Amazon will attempt to match or undercut everyone else in the market.” The other toy retailers will often react to price cuts by these competitors, he says. “You’ve got to keep checking prices.”

How to cut the cost

● Shop online via a cashback website. Register with Quidco and Topcashback and you’ll get money back each time you make an online order with a retailer on their site. You can also earn cashback in-store by downloading the Quidco and Topcashback apps and by registering your debit card with both cashback sites.

Topcashback currently offers 7.3% cashback on Argos to purchases and 4.2% at Toys R Us, plus lower rates across other major stores; Quidco is offering 7% at The Entertainer and up to 5% at Asda.

● Hunt for vouchers that offer online discounts at the till. Hot UK Deals and the Grabbit forum on Moneysavingexpert.com are good places to look. MyVouchercodes.co.uk currently has £10 off a £100 spend at The Entertainer and 20% off at Mothercare amongst others.

● Use Flubit instead of Amazon. Flubit.com allows you to get a lower offer directly from an independent UK seller for the exact same item you want to buy, reducing prices by 10% on average. You paste in the Amazon link of the toy you want to purchase and wait up to 24 hours to get a better offer. If you like the price you’re given, you can then make the order through Flubit. The process takes longer than buying on Amazon since each offer created is unique. Each seller has their own returns policy. We tested the site and found we could save between 8% and 12% on Amazon’s prices for most of the Dream Toys, saving almost £60 in total.

● Look out for promotions. For example, Toys R US is offering a £15 gift card when you spend £100 or more.

● Use your loyalty cards. Tesco is currently running a Christmas boost promotion on Clubcard points, where £5 of Clubcard vouchers will get you £10 to spend on toys in-store. Meanwhile, if you’re over 60, you can get 10 points (instead of four) per £1 spent on toys at Boots, equivalent to a 10% discount.

● Ask a foreign friend, relative or visitor to buy the gift. This is particularly relevant when it comes to the Frozen toys, which are sold across the world. Prices can be much cheaper abroad: Walmart, for example, is selling the Frozen Snow Glow Elsa doll in the USA for $28.88 – equivalent to just £18.10.