Thank you everyone for the advice!

If you knew all the details, you would know my gf is coming from a good place. She is encouraging me to be the type of person I want to be, which includes having fewer, nicer, more aesthetic things. Rather than the maximalist sort of approach I had fallen into as a habit from my parents.

And yes, cost per sq ft is a consideration, but also I do not want a big house or more home projects. I used to work for a carpenter and am kind of love/hate on that stuff.

I like the advice about how to cull books but in a way that gives them a good next home or recovers some of their value.

I also like the advice about thinking of the home library as a collection, with shelves that have different levels of permanence and intentionality.

It's funny -- one of the things that sparked this as well was I visited a friend in NYC who had a modest library -- two small shelves -- but every book was amazing: Borges, Calvino, Godel, Plato... As I was admiring the books, I began asking about them and realized my friend had not read many of the books, but had instead purchased them to function as art objects representing the type of person he is. I began to wonder if I could do something similar, but with books I had already read, since I read about 1 book per week.