Monitoring my alarm costs me under $30 a month, through a local company that responds physically if I don't call in or they can't reach me by phone. Not all alarm companies do that.
It cost my another $50 a month, for the two years I was away, for physical checks of the exterior several times a day and a weekly check of the interior. This included authority to contract emergency repairs on my behalf.
My lawn guy checked at least weekly and took care of exterior problems.
What is available depends a whole lot where you are. What is needed depends a whole lot where you are. Where I am, the biggest threat to be monitored is weather damage.
I know people who use house sitters. Some have good experience, some had bad experience. My house sitter didn't handle maintenance as needed, trashed the place and moved on when she found a better situation.
My snowbird brother moves between his two homes with them watched by neighbors, family, and lawn service/property management guy who takes care of maintenance inside and out. Property management services are available in almost any small city or larger.