I would do what you suggested. Talking with the landlord would be my first approach. Hopefully, the landlord can whip their new tenants into shape. I would tell their landlord that their tenants are not parking in the correct places and that your tenants bikes have gone missing.
I'm not sure how allowing your tenant to have a dog will solve or prevent this issue? A fence will be expensive but if you planned on doing it anyways might as well do it now. In addition, adding a fence can potentially attract more tenants when your property is vacant if potential tenants have a dog and are looking for a fenced backyard.
@Richard P. I would start with a conversation with neighbors landlord. I would look into a fence also. This will add protection to your property, increase the chance that you will have longer term tenants and make your property more appealing, possibly at a higher rent in the future.
Maybe get an inexpensive wifi camera system to catch the neighbors in the act.
I personally don't mind spending money to fix problems so that they don't keep being problems.
Good fences make good neighbors.
@Richard P. . Have you thought about security cameras? If we are talking stealing stuff (or taking things that don't belong to you), I would definitely get a good camera and document some of this for law enforcement. These folks are wrecking the neighborhood, including your own ability to do business. How many quality renters would refuse to rent in this location, if they saw this?
I don't know that your tenant will like it if they feel like they are being "monitored" in their back yard, but even a fake camera can go a long way toward deterring unwanted behavior by the neighbors.
I would not install a fence or allow your tenant to have a dog.
Neither will resolve the tenant problems. I would talk to the landlord and inform him that you will be calling the police on all issues related to the neighbour and have their cars towed if found parked on your property.
Playing nice and expecting positive results with people of this nature is a waste of time and effort. Likely hood is the landlord will be the same as the tenants. Do not expect any assistance from him in controlling his tenants.
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