Dead/dying tree in backyard

Was hoping to get some advice about how to handle a dead/dying tree in my backyard. I own the building/property. We had concerns about the tree last year but didn’t really think about it. This year the tree had no leaves even when all the neighboring trees were thriving. Now that it’s July, a little less than half the branches of the tree have leave. It was once a beautiful, tall tree, but we are now concerned about it being fragile and potentially dangerous. However, we don’t know exactly how removing a tree like this would work, since it’s an enclosed backyard. Also how much would something like that cost…. Any advice or similar experiences.