Possible topics could be a Facebook ads module, Instagram marketing, YouTube keyword marketing, using Facebook business and personal for your RE business....

The tracker eats your battery.  

Speaker was entertaining and kept you locked into the module and slide shows he was presenting. 

No maintenance other than batteries once a year and throw it away if it acts up.

You keep power on, smoke detectors that aren't battery operated will need to be active.The cost for power in the unit will be minimal you can unplug fridge, leave door propped open.Call your utility company, you should be registered as landlord for the property and in between tenants the power is reverted back to owner.You may be able to download the forms from your power company and or fill in online, or fax, each time a tenant moves in and when they move out.  

But I won't ever allow somebody with a battery or physical criminal record for the safety of tenants and neighbors.Interview Applicant:  Ideally you meet them in person and can answer any questions. 

I even placed a smoke detector in the kitchen but they just took the battery out.

Battery life of course.

I went so long without turning on my car the battery died.

Most anything within walking distance of the Battery, IMO no one is going to care about having or using a hot tub.