You may need an escrow or settlement company to act as an "independent third party" between you and the seller. Without having a third party involved, how do you know that when you fork over the money, you are going to get the deed? This is the type of service provided by escrow and settlement. They will hold your deposit and coordinate much of the activity that goes on during the escrow period.

Since this third party is very important to both you and the seller and you will both pay fees to this company so it is important that you and the seller agree on which service to use. Therefore, your choice should be included as part of the offer. Since you do not buy a home every other week or so, you are probably unfamiliar with companies that provide this type of service. Your real estate agent will typically a recommendation of whom they are familiar with or use regularly. You will have the authority to accept or decline the recommendation and include it in your offer, or make your own selection of who to use.

Keep in mind that the seller will also share this right and may have another preference and this may be a included as a point of negotiation in a counter-offer. It is customary that one side will choose the escrow/settlement agent and one side chooses the title insurance company. Always remember everything in real estate is negotiable.