Brownstone renovation

Considering a building in harlem with decent plumbing and electrical (from late 90s). If so, I would like to pull out carpeting and replace floors with real wood floors on two floors, update the bathroom on two floors and completely redo the master bathroom, update the kitchen on one floor and update, turn a small kitchen into a guest bathroom, electrical and plumbing to modernize as well as replace the stairs which are creaky and older. Please could you share your thoughts on approximate cost as well as some contractor recommendations. Depending on costs, I would consider putting in a patio or rooftop deck and putting in a/c (but not full central air)