I use a Guardline, and I like it, but I wish I could customize the alerts more, like naming specific locations such as ‘lower driveway’ or ‘back trail.’ https://www.amazon.com/gp/product/B00HFZUKGM/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1.
You could get a motion sensor light and connect it to a doorbell. That would also alert you to people walking in.