I should note that my scenario was exactly the same. I wanted to share location with family. Additionally, Traccar supports temporary location share links for friends if you’d like. You’ll need to self-host it- I personally set up the Traccar server inside kubernetes and used Traefik for reverse proxy and SSL, but this is not necessary.
You change how frequently checks are performed. Traccar runs a simple every X seconds pattern. Default is 5 minutes. On 5 minute pings I see a 15-20% drain over the course of 24 hours, which seems reasonable, given that I’m on GrapheneOS and not leveraging Google’s location tracking simplifications. If you’re not on GrapheneOS your battery usage for location tracking will probably be better. Just not private.