PJ Wade, writing at Realty Times has an excellent article titled, The Offer: There’s More To It Than Price
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In the article she states that all too often, fixating on price can cost you the deal:

• Sellers who decide that a specific dollar figure will buy their home and won’t budge from that bottom line may sell themselves short.
• Buyers who drop out of a transaction for a property they love because the seller’s counter-offer shocks them may be quitting before they have really started negotiating.

When a buyer makes an offer to purchase a house, condominium unit or commercial property, the purchase price is a prime consideration, but it represents only part of the total value offered to the seller. Problems may arise for both sides of the transaction when this fact is forgotten.

She then goes on to explain the other considerations of value:

Closing Date
The closing can be timed to provide benefits to the seller.

Inclusions and Exclusions
Non-real estate items can be included or excluded to benefit either party

Terms and Conditions
The conditions of the Purchase and Sale Agreement can provide more or less risk to the seller (or buyer).

Intent and Sincerity
How determined is the buyer to buy, and why? How determined is the seller to sell?

She concludes

Yes, price matters, but there’s a lot more involved in creating an offer that demands to be accepted. That’s why an experienced real estate professional is a valuable contributor to success. Professionals can calculate, or at least estimate, the seller’s net proceeds after costs related to the offer and deduction of commission. This information helps the seller accurately evaluate an offer to purchase. Understanding cost and benefit for all elements of an offer helps a buyer intent on ownership to create the best financial package possible.

She then advises the reader to re-read this post when submitting an offer. Good advice.

I have only given you some brief highlights. You should read the whole article. It makes a lot of sense and something to keep in mind when negotiating with a seller.