I spotted a solar powered wireless 'metal detector' type drive way alert on Amazon, but the reviews were hit and miss at best. That got me thinking about about a system I first saw in the mid 80s when I was still in Florida. I remember seeing the Winland Electronics Vehicle Alert System in catalogs all those years ago and from time to time ever since. The Winland system requires you to install a sensor next to the drive way and run (plus bury) a cable to a console installed inside your home. It's still around because it works.
The Winland system was always more expensive than what I wanted to pay, especially since I needed more than the supplied 100ft cable. Now days $400 isn't as expensive to me as it used to be. I'm older and I don't like surprise visitors as much, so I ordered one with a 350ft cable. You can click the picture above and see and read about my installation of the system.
I have to say making a trench 330 ft long and a few inches deep is a bit more work than I expected. The tree roots and crossing two creeks using flexible metal conduit added to the effort. I worked at it 3-4 hours a day until it was done. I used my hammer drill with a bit borrowed from Wally, and put the cable through the foundation below grade.
I made a counter out of a inexpensive pedometer to keep track of how many vehicles come in and out my drive. The counter works well. My idea of using a wireless doorbell to alert me if I'm working in the garage didn't work due to RF interference. I'll install a wired buzzer next time I'm pulling cable through the conduit to the detached garage, so I can be alerted if I'm out there.
I'm hoping for many years of trouble free service from this system. I'm sure sooner or later something will break the cable. Hopefully by then they be cheap wireless systems that work and I'll just get one of those.