Negotiating an offer, is it too late? after 13 years as a recruiter

It is the first offer in 13 months and I do not want to mess it up. I have been trying to stay organised about it. The hiring manager was friendly and open. Did it backfire?

If they say no, consider asking for something else, such as a review in six months.

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