How many trees are too many?

There is the house by my mom's that I HATE! Okay I HATE the yard, the man that lived there was insane, he kept adding trees and bushes to the middle of his yard with no rhyme or reason. Most people remove trees in the middle of their yard because it looks weird and makes mowing the yard a nightmare! So every time I would come home to visit this man had added more trees and bushes, it was ridiculous!! Late last year the man put his house on the market and I was so please because I knew whoever bought it would remove those stupid trees, I am pleased to announce that yes the trees are being removed!!! The downside to this, who would have known that there could be a downside to this, my mom’s neighbors have taken some of those damn trees and transplanted them on to there property line!!!! There is a line of Lilac bushes that separate their property and my mom's and they added like 3 more bushes(which match okay) then they added this Evergreen tree that looks exactly like a Christmas tree(and look utterly ridiculous)at the end of the line!!! I might know where we can get a cheap Christmas tree this Christmas!!!!