If you treat it as a small business, you ought to be able to claim some business expenses. For instance, you wouldn't be able to do that review job without a computer of some sort. So depending on the age, you might be able to claim it's depreciation value. The area of your house where you store the products, anything you buy in order to use the products (batteries, for instance, or gas for a lawnmower) count as a business expense. If you bought a camera to take review photos, that is a business related expense. The key is that it has to be something you bought just for that business of reviewing. If you use the camera for family photos too, then you have to go through the 'what percent of the time is this used for work and for non work' and that gets pretty tedious to prove. Keep receipts.
