What if a niche only has a few products over £300?

The average product price is an important factor to consider when validating a niche.

You should search across the product range of a niche and check whether there is a significant portion of the niche that contains products over £300. This will ensure that the average order value of your store is above £300 and therefore you are generating a good amount of profit per sale. This means that you will need to make less sales to reach your target profit per month. 

This is an important consideration so that you are not relying on a high volume of low ticket orders to reach your target profit. With more orders comes more administration and it is the same amount of effort to sell a £1000 item as it is to sell a £100 item.

You should also find out whether there are enough different products at a high ticket price from lots of different suppliers to mitigate your risk and make sure you can sign suppliers with the high ticket items.

To further validate your niche, consider whether direct competitors are selling lots of products at this price range?