Search Engine Optimisation

I have an e-commerce website which I have been doing my own SEO on for a while. I’ve got to 1st and 2nd on a couple of keywords but am running out of time to keep up with it and rank higher for other keywords. I’m looking for someone who can do this for me on a fairly regular basis to get me higher on Google for new keywords and with a small budget. My website is on wix.