Do you mean hosting a server just for your own personal use? Technical knowhow aside there are pros and cons.

Pros:

• You’re very unlikely to get defederated from anywhere and can control exactly who you defederate from
• You’re not at the whim of your server owner suddenly deciding to shut down one day
• You can decide whether or not to host communities on your server, in which case you’ll have control over exactly which ones get to be hosted there

Cons:

• You’ll need to search harder for communities to build up your subscription feed because you won’t have other users searching and indexing new things all the time, so you’ll be fairly reliant on sites like lemmyverse.net at least at first.
• Anecdotally I’ve heard that once you’ve got some bigger communities federated with your own, the database storage requirements can be surprisingly big. That’s just from off-hand comments from other admins though, I don’t know enough to comment or have any hard numbers on it.