Thank the writer and the company he represents for the honor of you and the choice of your person as a potential employee. Remember that offers on the job send only the specialists of strategic interest to the organization, they are not sending secretaries or couriers. Appreciate this attitude to you.
Inform the employer about the exact date when you will be able to begin his duties in the organization in case of full acceptance of the conditions listed in the letter. Usually it's prescribed position, the level of subordination, the employee's duties, salary, bonus system and benefits package. If you have any questions and objections, write it in your answer on the basis of proposals by the company will be prepared employment contract. Often as a proposal for cooperation is sent a document that requires acceptance. Signed in a timely manner, you automatically agree with the proposed conditions, in this case, you can write the answer.
Ask for clarification you do not understand the conditions (if any) prescribed in the proposal to work, for example, the system of payment at the time of the probationary period. Clearly specify your objections and suggest alternatives that you would consider. Not worth it, of course, to persuade a potential employer to attribute another zero to the amount of wages, but when it comes to moving to another city, settling the formalities at the previous place of work, then you can insist on. Agreed by you and the company wishes will be made in the form of the employment contract.
Refuse politely the offer, if you can't accept it. Don't describe the reasons why you want to use a common phrase "family circumstances", "I currently do not plan to change jobs".
Express appreciation at the end of the letter and wish the author offers about the job and the company he represents, and prosperity. Your signature and date.