You can often find second hand machines in excellent condition (sold by people who think they are too large after they bought them?). Mine was about €20.
I use bread mixtures from the supermarket which cost about €1.50 per kg and are good for two small loafs.
It depends on the type of bread you’re looking to have. If you just want cheap sandwich bread, a grocery store will be cheaper. If you want to have a nice warm loaf to spread butter or jelly on, it will be cheaper with a bread maker. I think there is an assumption that you would also have most of the ingredients on hand. Yeast is the only specialty ingredient.