HDD enclosure is a fine way to start, as long as you know it has limitations. Eventually you’ll probably need more storage, and it won’t scale. That being said, you can get 26TB hard drives now, it’ll be a while. Just make sure you plan out how to back it up. Remember the rule - if you can’t afford to buy a backup then you can’t afford to do the project. Make sure you have backups in mind.

If you decide to upgrade to a full NAS solution later also remember that during that migration you probably will need to use new hard drives while migrating as your current ones will need to be copied from to the new NAS, meaning you will probably end up with a few redundant drives. Not a huge thing, but there will be no “in-place” upgrade. It all depends on where you want your homelab to go in the future.