Easy resolution: 1) Put a sign in your yard (front and back) that say "No Trespassing". 2) Put a sign on your property that say "Security Camera" 3) Keep a video camera near your door so that any time those women or anyone else returns...make sure that you're recording (documenting) your conversation with them and let them know you're recording them. 4) Even if they leave your property, you should still call the police and tell them you told the women to leave and that it was private property. Give the cops the women address so that the cops can give them a quick visit. If it happens again...call the cops again and this time tell them a little lie...that it looks like one of the trespassers was carrying a gun. It gets the cops a little more interested and a little more aggressive in their next visit. 5) Install motion detector lights on your property and motion detection security cameras. Get one that only takes video when motion is detected and sends the video automatically to your email address and/or cell phone. Also, it you should be able to log into your security camera from anywhere in the world to view what's going on at your home in real-time. I've had problems with a neighbor and I then did all the above for less than $800 and the problem stopped immediately. By the way, any professional dog sitting business in your town ? If so, use it especially if your local weather forecast is bad weather.
Personally, I'd stop having communications with them. Kindly instruct them to stay off of your property or you will involve the police. If they continue to bother you, I'd look into a restraining order for harassment. You sound like a reasonable person, but I would simply stop being so nice to them. I'm not saying being mean. Just don't have conversations with them. As long as you are following the law and taking care of your dog (sounds like you are), screw them. Keep a log/notes on any conversations or encounters and get a camera. Sounds like they are busy bodies that want to get in everyone's business.
I think you take care of your dog and love him. To leave him on the chain outside to go to work is stress for the dog. If you keep him on the chain, the dog know he can not run away to defend if the strange dog come to your yard. Your dog know if the strange person come to your yard he can not run away from them too. Your dog know this. So he is puppy now and very sweet. But he will grow to be afraid, have fear, and feel aggressive for because he do not have freedom to run away. Why you do not put your dog in the house when you are go to work?
I am saying your dog is on the chain for a long time when you go to work. Your dog is can not defend if some people tease or abuse him. He can not run away and he can not attack if the people know your dog have only small space to move. Your dog know that too. Your dog know if stranger aggressive dog come to your yard, he can not run. I am saying your dog will have fear and be so afraid, and not social if you put on the chain for many hours every day.
Personally I would not chain a dog. If a dog has to be kept in a porch or something until a fence can be built then walking it once or twice a day might be adequate to keep it from going crazy.. Los Angeles County has some laws about chaining dogs, not sure if it's illegal or the chain has to be a certain minimum length or what.
For hundreds of years dogs have been kept outside. We always had dogs growing up and my dad had a strict no dogs in the house rule and our dogs did good. He did let us bring the puppies in the house to play with though. We had one dog that wouldn't get in the dog house no matter how bad the weather, he had a thick coat so he did ok in the winter and Dad set up a heater for him outside during one bad cold front I remember. But he stayed outside. Any nosey neighbor would of bitten off more than they could handle if they though they would chew his ass out and lecture him on how to take care of his dog. He didn't gossip or butt into others business and he wouldn't take the crap like those ladies put out. But those were different times in a rural part of the country.
Take care of the dog. Learn if animal control can legally enter your land to investigate. Plant a line of sight hedge. Post the land. Get a firearm, walk outside with it when trespassers are on your land. Security camera with night vision, perhaps a game camera. Thank them for helping your dog-likely too late. Get rid of the dog, you lack the resources to care for it. You are messing with crazed womens, good luck.
My wife and I bought this as our first house for a good deal and did a ton of remodeling work to it ourselves. We still have quite a few finishing touches to do like trim work and a little more painting, but geez I am about ready to finish this thing up and sell the place. We have quite a few odd neighbors. First we have an issue with the people across from us. It is about an 70 year old woman and her 40 year old son who is schizophrenic and not on any medication. He would stand at the road screaming and crying all night long. It freaked us out because he would just sit there and stare at us from the end of their driveway anytime we were in the yard or would wave at him. Not to mention it is hard to sleep when someone is 50 yards from your bedroom window screaming for the voices in his head to leave him alone. It is crazy the things he would shout. The neighbors told me he was picked up by the police almost every week for awhile because he would wander around the neighborhood screaming and crying. I understand he can't help that he has that disorder, but him taking medicine would sure help. Anyways I take night classes and don't get home until late at night. My wife was constantly freaked out by this guy not to mention the disturbance. So we finally said something to his mother and now he is 100 times better (back on his medicine). He is friendly and everything and doesn't come out their screaming much anymore and we are fine with his mother as well. She was rude before but is very friendly now as well. It worked out. We then randomly have people walking to our back yard to pet our dog. Then we have this whole thing with the dog and these crazy women take place. They keep coming on our property. Now last night I look out the back window and see another neighbor woman (about 55yo) is at another house (not hers) walking around peeking in all the windows while they aren't home.....WTF is it with these people! Everyone is old in the neighborhood except one house near me. The guy and his wife are in their 40's with two kids and we get along great. Super nice people. The rest of the houses around us though drive me nuts! Except the woman and her son. Everything is resolved and they are nice. Maybe it is because everyone has lived there a long time and we are the new people and are young, I have no clue. Regardless it is getting annoying.
Older people don't handle change too well. They want things to be predictable. You represent a disruptive force in their lives. Also, it sounds like some of them have way too much time on their hands, so they get into stuff that is not their business. I would like to own the company that installs fences in your area. Because it sounds like there is a lot of potential business there.