Well, how easy you find it depends on your skills: You can take the official bitwarden appliance as docker-Container, this shouldn't be too hard, but consumes a lot of resources, so I am not shure if this runs on a NAS at home smoothly. However there are other solutions like rubywarden.
Enpass with its easy WebDAV Sync to my self hosted Nextcloud surely is unbeatable.
As long as the enpass people are unwilling to let us pay for a "Non Google Play" full version, enpass is out of the race for me.
Would be nice to hear an official statement regarding to this, so we can decide if it is worth a little wait -- or to move on.