Heat zones

I have two story plus partially finished basement 2500 sq foot home that is well insulated and heated by an air heat pump. Two ?
1)Is it more efficient to heat the basement so that the upper two floors aren't losing heat to the basement. Currently the vents are turned off in the basement
2)I understand that there are set back thermostats for my type of heating and that they are "quite expensive" compared to a conventional set back. Are they worth the investment for the average home owner and can a reasonably competent plumber/electrican/home handiman install one of these?

Is the floor between the basement and the house insulated? If so you should be able to close it off and save on the heating bill. If not you will feel the cold. When you close off vents you necessarily get more air to the rest of the house. A lot of times you get less total air out of your duct work because the pressure increases. If the pressure is too high the air handler won't push out as much air. Weather it will benefit you cannot be answered on this post. There are too many variables. I don't know what you mean be "set back thermostats". Most t-stats can be installed be a handy man. Make sure he turns off the power first.