Thank you all in advance for any input. I'll really appreciate it.
I have bought a little house (my life long American dream), guess around 35 to 50 years old and in very bad condition. It is safe to live in but costs so much for heating and cooling. I am thinking to replace the windows but love the look of old windows. I am wondering if there is any ways to safe to old windows but improve air-tightness with a modest budget. What are the pros and cons of buying windows and installing services from places like Lowe's / Home Depot vs local window business.
Since I can't perform the work myself and have very limited resources to improve my home, I need as much of advices as I can before I make the move. So thank you for your words.