I am retired and faced with very large heating bills. The weather in NJ has been quite cold and snowy for us. Our home was contractor built
in 1966. 2x4 walls with 3" on insulation. The windows are wood but not as tight as today, but the stroms windows leak to a point that we get snow
between them and the window. The house is a colonial salt box, The front is one storey, two stories in the rear. There was no insulation in the frount. I have tried to put some over the years but not sure how much good it really does.

With limited funds what is your guess as to the place to start.

Thanks
Tom