There are many small details that are involved with writing business letters. When writing them the one thing you must keep in mind is that they really are different in that they must be super focused and targeted to one specific idea at a time. No business letter should deal with too many, multiple issues unless asked for or specified as a requirement.
This is a little known secret. Most people do not realize exactly how much emphasis this can place on your letter getting any kind of positive acceptance. Results are genuinely most important in matters of business letters. They should also be targeted in just this way.
In some ways business letters can have a huge impact on whether or not another business or company will want to work any further with the sender. That is how important these letters are. This can sometimes be a huge amount of weight and responsibility on the one writing the letter. It is a lot of pressure. So the best way to write it and write it well is to forget about it altogether and just write.
Thinking on it too much will ruin the entire writing process. A good writing process must flow easily and fluent. All writers have their own unique process and ways they handle different writing ventures. The worst outside issue, in writing a business letter is the pressure induced by formality.
A lot of pressure put on a writer and his project can be a bad thing if the writer is not used to it. So idealize that the writing is not very important. In fact call it informal. Did you know that the best written business letters are written with an informal tone? People like to be talked to in relaxed tones it eases their mind and pulls an easier decision out of the situation.
Many people are unaware of just how effective an informal business letter can be. Except for the writers who write them.