Don't doubt yourself:)

My suggestion is: start off doing the reviews and getting the word out there. It doesn't have to be perfect. As you gain traction, confidence, and understanding of the market - you can always go back and update the reviews.

You will surprise yourself; the journey of learning the industry is often the motivation to provide good content and value for your readers. Those who fail, often put the monetary aspect in front of it.

Hope it helps and good luck!