Translation of Zwischenhändler

A proposal for our further cooperation: I will translate your texts in English and you translate my letters into Spanish. I will focus on spelling and grammar, and I will correct your sentence structure.
As mentioned in our conversation, I will send a more detailed description about all the other exercises. As indicated previously, I believe in your technical skills and in your talent.
I want learn Spanish because of my girlfriend from Guatemala. She is from Latin America. And of course I want improve my grammar too. I like to hear it, but speaking is still hard. Hasta Luego.