On-page SEO for a website

I have a website (https://www.snazzyholic.com/) which have about 270+ prouducts, and a few blog posts on a Wordpress WooCommerce website. I want to have someone the do the on-page SEO for me. I don't know if my website need the full SEO (I mean, SEO on products and SEO on blog posts). Please break down the following:
1) the cost and time and what you will do on full SEO;
2) the cost and time and what you will do on products only
3) the cost and time and what you will do on blog posts only

Please tell me the experience you have on this SEO sector.

P.S. I have limited budget, so I can't pay hourly rate if the hourly rate is high.