Hello hazel! hope you doing well. I was having the same concerns for my online business of selling used electronics and then I hired a digital marketing agency that has done social media marketing and search engine optimization for me, I wanted to do PPC of my site but they told me that PPC will just work until I got the budget for it, whereas SEO is a time taking process but will be done once and it will bring relevant traffic on my site who are interested in my products like forever and they did my social media marketing on Facebook and Instagram by just boosting my posts over platforms. I was unaware of the power of marketing before but then I have seen it myself by knowing that my sales have been increased more than 50% and my website has been ranking on google. I am looking forward to investing more budget in marketing in the future.