Who officiate a vow renewal?

You can if you want to. Since you don't need anyone to legally officiate, you can have a close friend or relative officiate the renewal without having to get ordained or anything. Sometimes I feel like it's all the more special when someone who really knows you gets a chance to speak about your relationship.

You could hire someone or you could ask someone in your lives you feel would be good at it. We had our friend conduct our ceremony and she was amazing. She put a lot of work into helping us write the ceremony and it was super personal. Everyone said she should get her license and start a side gig doing weddings lol! If you don’t think anyone in your life could fill that role you could definitely hire someone. We spent as much on her gift as an officiants fee so it wasn’t about saving money for us, it was about the personal touch.

I don't think hiring someone is necessary. You could ask someone that has had a positive influence on your lives together to "officiate". I think it's more meaningful that way too

Since they don’t need to be an actual officiant, you could just have a close friend or family member perform the ceremony for you.

You don't need one however youll can

Since there's no legalities involved, you can have a friend perform the ceremony or spend extra for an officiant. It's entirely up to you.