My 2 cents...

I agree with Brandon... I wouldn't pay for a demo.

I just can't grasp the idea of A LARGE NUMBER OF PEOPLE wanting to demo these in the comfort of their homes. If you do only a couple of demos a month, it is not worthwhile to devote that much time to this.

Also once you start demoing (recommending) a product, then there is that possibility that they will call you back and you have to answer other questions that may take up more of your time. USD 75 is too little money once you start counting the hours you will have to spend travelling back and forth and doing all the work.

Good luck in your pursuits !