If you are away, your home may become a target.
A remote “house sitting” service that visits your home every day (at different and unpredictable hours) and produces “signs of life” so anyone watching it will think people are regularly there.
You can’t have potted plants in your vacation house because there is no one to take care of them.
A service that helps you design which plants go where in your vacation house then houses your plants and takes care of them on their premises. Before you arrive for your vacation, the service will ship place them in your house at their designated places.
If you walk almost anywhere, you will see plaques celebrating and informing you of interesting people and facts regarding many places (buildings, parks, etc.) There are much more of these than you see on these plaques and many a place where there is no plaque even though it has an interesting history.
An augmented reality app that when pointed at such a place gives you a list of all the interesting things that happened. Famous people who lived there, historical events, etc. You just point it at a building or even a few buildings, or a whole park, and see the list pops up on the screen beside the place you point at. You can them click on any of these to get many more details and the story.
A drone that knows how to go around the house and stream a video feed can be useful. For instance, you can check if you left your keys at home, or see if the stove was not left on, it can alert you if there is an intruder, etc.
A drone that can navigate the house (using the visuals it analyzes from the video cam, the map in its memory, etc.) Anytime you can remotely activate it and tell it to go somewhere in the house and show you what’s there. It can also be programmed to react to certain events, like sound, motion, external input (alarm system), etc., and alert you when the conditions you requested are met. You can also program it to do “the rounds” from time to time as an extra security measure, and alert you when something is out of order (like a change in the what it sees compared to last time. When not active it can land on its charging mat to recharge.
So tenants can try and be considerate to each other with the times they can practice.
Have an online weekly schedule, where people who practice musical instruments can fill in how many hours they want to practice every week, and all the times they can practice day by day, hour by hour for a typical week. At the same time, other tenants can fill in times they absolutely have to have peace and quiet. This will make it easier to find practice times (if the tenants are considerate, to begin with.)