How much room is there after an offer? - 12 months and counting

It is the first offer in 12 months and I do not want to mess it up. I have read a lot of threads here and could not find my exact situation. The hiring manager was friendly and open. What wording worked?

Most employers expect a short conversation. Mine did not even blink.

Thanks for writing this out. I went through something close to it last year, and it got easier once I kept a simple log of every call and form.