Here’s one I’d prefer you to do on you own.
To be safe, you should touch up your chain every time you go out. To do it that often, you need to be good at doing it yourself.
I use the Granberg G-106B, it used to be $30, looks like it climbed a little bit, still worth it.
I think any bad reviews are by people who aren’t using it correctly. It’s not rocket science, but the included directions are rather sparse.
Here you go: