The best way to get the house, which is your main goal, is to know what the real market price is (objectively), which your agent can advise you on by providing comparable sales in immediate area. Your agent can also show you how the value of the property is calculated, based on appraisal principals.
If you are buying the house for yourself, you have to decide how high a price you are willing to pay in order to get it. Sometimes, buyers love the house so much - they are willing to go higher than the market. Usually, this happens after the buyers have been looking for a while and they didn't fell "comfortable" in any of the houses that they had seen prior to finding "the one".
Or, they made offers, but their offers were too low for the market, and they didn't buy as a result.
Once you decide how much you are willing to pay to get the house, have your agent do some recon for you - to find out about what activity is going on re. the house in question. Have him/her ask the listing agent questions like: How many people came to see it? How many buyers came more than once? Did the sellers entertain any offers? Is the seller motivated or he is just testing waters? It's unlikely that the listing agent will tell what the other offers were. They are not supposed to, anyway.
But, some of the info you could get asking "allowed" questions could help you in your quest for this house.
There is no language to motivate the buyer to come back to the seller.
However, the listing and the selling agents should be able to create a good enough relationship to make the meeting of the minds (buyer and seller) possible. In other words, if you instruct your agent to make it known to the seller that you really love the house and are willing to work on a fair price, and your agent stays in constant touch with the listing agent, and your offer is prepared meticulously (showing that your agent is a professional - which makes the listing agent's job easier), and your assets/pre-approval are in perfect order), you should be able to buy a house. There are other tricks of trade - I'm sure your agent can help you in this process.
Sometimes, a letter from the buyer to the seller helps also. In the letter, you describe how you fell in love with the house, and you tell the seller about yourself and your family, and how long you've been looking and how happy you are to find it, finally...
If you are buying the house for investment, then work your numbers and decide if this house is worth buying. If not - next...
Hope this was helpful,
Beachfront Realty, Inc.