When trying to get more privacy for your back yard, two normal choices are fences and hedges. Both will work but have positive & negative attributes.
Hedges obviously look more natural and in my opinion are more pleasing to the eye. But they do require fertilizer, water, and trimming. The trimming is hard work and not something senior citizens want to do. I don’t even want to do it sometimes and I get paid to trim them
. The trimming is not so bad if you can stay on top of them but if you are wanting them for privacy they need to be big. That means trimming up higher which is even worse than normal trimming.
Fences are the easier option if you need instant privacy. They come in different colors and styles also. But no matter what material they are made of they will need cleaning. I don’t care what the idiot selling the fence tells you. If it is outside, it gets dirty, period. I’ve had customers say that real estate agents told them their vinyl siding would never need cleaning! I personally like wood. You can stain it or paint it. So when you tire of one color just change it up.
Both options cost money to maintain. You can choose not to maintain them but your results will not be good.