Request to work from home letter

I am looking to hire a freelancer to write a letter for me that I can present to my employer, requesting to work from home permanently. I dont mind going into work 1-2 times a week but anything more would be hardship as it take any where from 1 and half hours to two hours each way. I was under the impression I was an work from home employee but now being ask to come in 3 days a week. The letter should have a blend of both formal and informal tones, and should be detailed, citing all the reasons and benefits in my current work that make this option feasible and preferable. I would like it to be attractive and professional-looking, as it is something I will be presenting to my employers. It should still, however, have a personal touch to it. Please let me know if you have any questions. Thank you for your help!