If you have idle land and you would like to make money off of it, then consider a cell tower lease. Note that this will only work if your property is in a strategic location for such a structure.
This means an elevated site that is in dire need of new towers to improve the service. It may need to get permission from the local council. Engineers will also assess the site for suitability before building as well.
There must be no issues with regards to ownership since leases like this are long-term contracts. They may span several decades in order for the tower builder to recoup the cost of construction and installation with their own earnings.
If successful, then you can have a monthly cash injection without doing much. However, this may bar you from developing your land in certain ways that may affect the tower’s performance. Read through the terms carefully.