Totally homemade using very good instructions from a syrup maker.
Cost was under $300.
I process the sap as I collect it and don't monitor temp. I do have a hand held refractometer (~$100) to measure sugar content (for wine making) and use that to measure the the sap and concentrate.
Usually I keep the sap outside so it will stay cold. If it partially freezes you can process the concentrated liquid sugar solution and toss the ice cube, as that is straight water ice. If it comes inside or gets warm outside, the sap can get guys growing in it who eventually devour the sugar and leave some interesting flavors.