I need to know how to write a demand letter to an insurance company due to a huge difference in the amount from both adjusters

The demand letter should outline the facts of the situation.  It should then apply the facts of the situation to the pertinent policy provisions at issue here.  For example, if the damage is for personal property, you should quote the personal property sections of your policy, etc.  You can also emphasize that you have complied with all policy provisions (if that is true).  Then you can go into detail about the two adjusters and their differences in damages.  Next I would insert some state law to help back up your claims and/or that provide guidance on the issue at hand.  You can search for cases using the legal network that the attorney's office uses (if that is authorized), like Lexis Nexis, CaseLaw or Westlaw.  For example, if I were using Westlaw, I might try searching "differences" /20 "adjusters" /20 "insurance" and see what comes up.  That is going to pull up all cases (depending on what jurisdictional areas you pick) that has the word differences within 20 words of adjusters within 20 words of insurance.  That might provide you some information or backup on this issue.  Then, wrap up the letter with the hardships (if any) you have incurred as a result of the damage you incurred and the insurance companies failure to pay the claim.  Be sure to include a timeline if it will be helpful. And finally, make a demand and ask for a response within x amount of days.  And, of course, let the attorney who will be sending the letter review it and make any recommended or necessary changes.  I hope this helps.  Best of luck! NOTE:  This response is general in nature and should not be considered legal advice.  No attorney-client relationship exists or is formed in this response.