@Stacy Morris Is your goal to get the seller to list their property with you as an agent? Or are you looking to purchase these as investments and keep them off market? Obviously, the letter will have to be different depending on the goal.
In either scenario, though, you want to be straight to the point. People most likely aren't going to read a full page letter. For example, if you're looking to purchase the property, maybe the letter looks something like this:
"Hi (Insert seller's name),
My name is ______ and I'm an investor in the area. I drove by your house the other day and would like to make you an all cash offer. Please call me at ______ to discuss.
Look forward to hearing from you.
Best,
______"
This is obviously just an example, but hopefully it gives you some ideas. Be prepared for when they call back - you should be trying build rapport and to set up a day & time to go see the property.
Hope this helps and best of luck!