I would really go look at some screens until you do you will not understand. the main factors that make screen more expensive is thickness. Will the screen remain flat over time. Materal, how smooth it is. Light just because it is a white 1.0 materal they are far from equal so are just more colorful and have a greater depth of field. You really need to AB screes and maybe order samples of the materals. It is amazing how many materals are not flat and we are going to 4k projectors now most of the lower end screens willn ot hold up.
Note: Any posts are of my personal opinions and not to reflect upon any business.