My business is based on OSS; people are used to no support. I've tried to guide my customers to open issues and stackoverflow questions to get a response from the community. This makes for a nice historical archive that others can search and find similar questions and answers.

I explicitly state in my support policy that emailed questions can take 48 business hours to answer. I take my laptop with me on vacation to answer support questions every morning. The rest of the day is free.

You could also contract out support for a week if you really want to avoid the laptop. Pay a contractor friend $$$ to answer your support emails for a week.

My main issue is that collecting money takes as much time/email as support. ~30% of my customers have some need for a manual touch during their annual renewal: forgot password, change email, billing question, etc. My first hire is likely to be an AR person who can handle that administration.