On these types of letters use a logo on your envelope, at least 28 pound paper, Personally I would do a linen, and always a first class stamp and live (real Person) handwritten signature and address...

Also the logo, envelope, and cover letters look very professional if that helps.Any feedback would be great or I'll just conform to wholesaling inc. haha.

I think the key is to also put the letter in an envelope with your logo when possible.Happy 4-plex hunting