I would say that as a one person founder, know that you cannot ever get 100% uptime and live with it. In the most simplistic sense, you need to sleep 8 hours a day, you cannot live your life constantly stressed about uptime. Just generally have internet access and sometimes your service will go down.

On the set up, try your best to solve issues and use tried and true hardware, but things go down sometimes, even big sites like Google, Facebook go down, there is no silver bullet, you can only improve on your past mistakes.

Last, try to find some remote help, on a contract basis, it's not that expensive and it can help alleviate a lot of your stress.