The prices of weight gainers vary. It depends on factors such as quantity, quality and whether you buy them in stores or online.
If you already know what you want, find out if there is a discount code from influencers at the moment, which can often save you a few percent.
The price range is between €6 and €30 per kilo. In general, it's not just the price that you should look at. You can also consider quantity, quality, recommendations or reviews when making your decision.