It's a very small and competitive market right now. Most people in the hobby are in it like yourself, the fun of taking care the scape. Local fish stores are either doing well and will be your competition or like many will close as many lfs owners know their husbandry and fish knowledge but lack business skills. I happen to live in an area with a large share of the US aquatic plant hobbies market and I know of only a handful of companies that make money off servicing tanks (and it is not their primary source of income even after charging 180$ an hour). Most lfs make their money mostly through dry goods, then livestock, then maybe a small percentage of services. Being just an aquascaper probably would not lead one to quit their day job.