I've been through SOC 2 Type 2 in a company with ~100 people. I think it'd be in some ways simpler as a solopreneur, but still a lot of effort. You won't require as complex controls and you don't need to communicate between different parts of company, but it'll just be yourself doing it all.

On a positive side, you won't have to do 100% of SOC 2 Type 2. The only required part is security if I remember correctly. And a lot of it is best practices that need to be in place anyway. If you are using an established cloud provider a lot of it is in place through their certifications. Some of the controls can be "silly", but generally not hard to put in place. I'd try to figure out what are the minimum nr of controls required and see if that is doable. Pretty sure auditors will give a discount there if the scope is smaller.

It can be somewhat useful for the company if taken seriously, as it can point out weaknesses in processes. Although I agree with other comments that most of it is a checkbox exercise than something that provides any real guarantees to the client demanding it.

I also don't know if getting through it with <20k $ is something that is feasible. Before doing SOC 2 we relied on the clients' security questionnaires instead, so maybe something to always ask about. Usually they were able to make an exception and allow it, although the % started shrinking over time.

Edit: Also, the auditor makes a difference. Pick one that understands small companies. A corporation auditor will get confused with "segregation of duties" if you are the only person in the company.