Though the differences may be few, when the embassy requires you to submit a sponsorship letter, by any means, do not submit an invitation letter instead. Boundless prepares you for success. This is often the easiest way to request the letter.
Have the ability to financially support yourself during your trip to the United States. However, do not go way too much into details giving unnecessary information as, where you will be eating breakfast each day and how much each breakfast will cost to you.
However, the process to getting a Schengen visa is not an easy cake. With Boundless, you get the confidence of an independent immigration attorney who will review all of your materials and answer any questions you have — for no additional fee. The letter is written by the sponsor, who explains their relationship with the applicant, and the costs they are going to cover.
When the sponsor is done writing the letter for the applicant, he or she should sign it at the end and send it to the applicant alongside with the supporting documents.
Actually, it is, if you already have a clear idea what the consular officer wants to know. Any amount that can justify the overall cost involved to support the trip and your financial ability to take care of the expenses related to trip will do.