Since it is a relatively simple product, you should not expect to pay hundreds of pounds for it. A manual scarifier is significantly cheaper than a motorised or electric model.
The price of the product is strongly influenced by the above criterion, but in addition to these, the brand is also a big influencing factor. Well-known and high-quality manufacturers offer their products for sale at a higher price.
Generally, higher-priced products have a wider working width and more blades, which speeds up the work overall.
The above table shows well that a lower quality manual scarifier costs almost five times less than an electric one. Of course, using an electric tool is much more convenient, but even with a good quality manual lawn aerator, gardening is not much more strenuous. And besides, it costs almost half as much.