We have just made an offer on a house. But first we looked at all the houses that fitted our requirements or nearly in terms of type, location , size etc. We also got a list of asking prices since the houses were on the market.
Having visited about 20 properties, we then narrowed our choices to 3/4 houses and revisited. Talking to the agents, we got an idea of selling prices which had been accepted on a number of houses in the area. This gave us a broad figure for what the houses were worth to us, we deducted 10% and made an offer (without any regard for the asking price!) . After a bit of negotiation, we settled on a price that suited both sides.
You have to put in the groundwork, if you are goiing to be happy about your offer - otherwise you may feel cheated for paying too much.