It feels like there are more and more buildings that are really run down.
I think there is an increasing number of buildings that are deteriorating in both the cities and countryside.
1) It feels like there are more and more buildings that are really run down in the city.
「都会に荒廃した建物がますます増えてきている気がする。」
run down で「荒廃した・荒れ果てた」という意味があります。
more and more で「ますます（多くの）」
2) I think there is an increasing number of buildings that are deteriorating in both the cities and countryside these days.
「最近都会でも田舎でも、荒廃した建物（の数）が増えてきていると思う。」
deteriorate「悪化する・退廃する」
an increasing number of ...「増加する…の数」
ご参考になれば幸いです！
日本 
