DIY wins when the site is small, your time is flexible, and brand risk is low. It can teach you enough HTML and CSS to move fast later. Hire when any of these are true: you need a tight brand system, you want Core Web Vitals in the green from day one, you need accessibility checked, or you expect press and investors to hit the site soon. Maybe split the work. You write the copy and supply assets, while a partner designs the system, builds the templates, and sets up maintenance.

I think that mix gives you control and a clean result. If you go that route, ask for a fixed price for design and build, then a small monthly retainer that covers backups, updates, and a set number of edits.