Stranger pulled up in front of my house

Hope this is the right subreddit to post to

Had a guy a little before 7 pull up in front of my house and knock on my door twice. I saw he left with papers in his hand and what looked like a walkie talkie on the side of his pants. He was dressed casually. He drove off and then a couple minutes later he drove past my home again going the opposite direction. He intentionally slowed down, and tried to get a glimpse of my home before speeding up again and driving out of view. Maybe I'm a little paranoid but saw another smaller vehicle drive past my house some moments later and he looked into my house as well but didn't slow down.

Really worried cause this guy clearly targeted my house. Have no idea what he could want. Legal? Financial? Etc? Is he a PI? We are not engaged in any illicit activities. It's creepy and I'm worried it'll happen the next day.