How much room is there after an offer? - 13 months and counting

I want to negotiate but I am afraid they will withdraw. There are 7 people counting on me, so I am trying to be careful. The benefits are decent. Did it backfire?

Thanks for writing this out. I went through something close to it 13 months ago, and it settled down once I kept a simple log of every call and form.

Keep everything in writing and save the confirmation numbers. It made the follow-up calls so much easier.