What size level should I buy for general home use?

Across the reviewers and trade subreddit threads we read, a 48-inch box-beam level is the most-recommended single purchase for general DIY and renovation work, it spans most doorways and cabinet runs. Pair it with an 8- to 12-inch torpedo level for tight spaces, electrical, and plumbing tasks. If you only do small jobs (hanging shelves, pictures), a torpedo alone may be enough.