1. On app level
Running an app on multiple servers isn't terribly hard. There are techniques which are difficult to understand and implement, but there are also some basic techniques any one can use.
Learn those basic techniques. If it's not enough, then yes, you'll have to find a freelancer or to hire a developer.
2. On infrastructure level
Running servers yourself (read "at home") is very difficult. Most of the small companies which believe they have their data center are doing it wrong. Their "data centers" are not secure, badly managed, not protected against problems with power, etc.
Many developers, including myself, have a PC at home which runs day and night. We call them servers. They are not, but it doesn't matter, since it's funny to say: "I have a server at home".
Other people are using hosting companies, which most often don't include any scalability. If you're intended to use a fixed number of machines forever, you're lucky. If your app starts to be very popular, issues arise.
Cloud as a technical term, i.e. something like Windows Azure, not *cloud" as a marketing buzzword, like iCloud, helps you to solve that. You can easily scale the infrastructure from one to hundreds of servers in a few minutes, then to scale down again if needed.