While all the advice is good . The most important questions are.
1. Is this an investment
2. Is this for a rental.
3. Is this a great location.
4. A second Home or 1st Home
Once you have answered this question , then go to comparables ,condition , resale or rental value. All of these will also play a part in the process of how much your willing to spend.Then once you have all the facts , make the call to a realtor and go over the process.If you don't have the time, contact one now and allow them to do the work and go over it throughly with you before you submit an offer.
I've seen banks accept HALF of the value before, you just never know...plus, they can counter your offer if it's too low.