Neighbors changing my channels

I caught some man-child showing his friends how to change my tv channels using the universal remote outside my door. Apparently news gets around and two new neighbors are constantly doing this also. One evening I watched my tv scroll all by itself. One culprit had the audacity today to ask me if they could park a little closer to my front door!! That is one part. The other part is, since this is possible, how can I prevent neighbors from free loading on my wifi and cable? Also they are able to turn my smart lights off and on with a car lock remote! Tenant before tried to run a cable from the back of the building to free load cable. Dangerous people! Thanks.