Need help writing a letter to owner of 4 unit building

[Hannah Trueblood]

Hello BP family! I have been following BP for many years, and I am finally taking the plunge to invest in my own properties! 

There is a 4 unit building that i have had my eye on for a long time. I will need to use creative financing to purchase. 

I did some digging on the owners and they are in their 70s, have owned it for a really long time, and they do not have any other properties besides their personal residence. 

I want to write a letter of intent, introducing myself, explaining why and how I want to buy it with seller financing (sell your home while still making money off it monthly) but I am concerned about coming off as “scammy”. Anyone here have any advice on what to write and how to write it to accomplish my goal? Thanks so much!