How much storage should I get for a modern MacBook Air?

Regarding the MacBook Air: Get at least 512GB, preferably 1TB. 256GB is not enough unless you live entirely in the cloud — modern apps like Xcode (15GB+) and Photoshop (10GB) eat space fast, and macOS itself takes about 20GB. 512GB is the sweet spot for apps, local media, and projects without anxiety. If you do video work, music production, or keep lots of photos, go 1TB — you can’t upgrade the soldered SSD later.