Affiliate Marketing Secrets

I am an American living in Stuttgart, Germany in the very early stages of considering business opportunities that I can work not only while I live here for the next few years, but one where I can continue to work the business when I move back to the states (Southern California). The two business opportunities listed in my title are the broad areas that most interest me.
With both areas I am more interested in the ‘representation’ of niche manufacturer products or travel packages.
My background is in sales and marketing (Sports and Media). While I currently teach Business English at German companies, unfortunately I’m still not fluent in German or any other language so this concerns me although in most cases I can have a native speaker handle communication translations.
So, I’m throwing it out there just to see what some of your thoughts are – the pros and cons, your experiences, etc.
Thanks in advance!