How To Write A Proposal Letter Asking For Money . There are countless foundations out there with money to give. If there are other accounts on file, you should also mention it in the letter. Donation Request Letters Asking for Donations Made Easy! Donation from www.pinterest.com.mx As you have gotten better and quicker at delivering your work, your time spent has decreased and, in turn, so does your income. The letter is written in a formal tone like other business letters. An investment proposal letter can be described as a summarized version of the company’s future business plan, written in the form of a letter.