I've been using Fiverr for a while, and it's been a lucrative side hustle for me. I offer digital marketing services, and let me tell you, the demand is constantly growing. I started by setting low prices to attract initial clients and gather reviews. Over time, I've been able to increase my prices and offer package deals.
If you're serious about this and want to scale up your earnings, I found this article on how to make 10k a month pretty enlightening. It talks about diversifying income streams and really maximizing your earning potential, principles that could definitely be applied to your Fiverr or Upwork gigs.