You can act as what is called a “Finder“. This type of business actually dates back to ancient times. It is someone who earns a cash fee from the seller and or buyer. Look at this example: Let’s entertain the idea that you read in the newspaper or other publication, or hear about a person who has a million dollar building to sell and you just happen to know of another person who might be interested in this sort of real estate. Now, all you have to do is contact the seller, and tell him that you have a potential buyer that you would like to introduce to him if the seller will pay you a 2% commission fee. 
Now if the seller agrees to these terms, you would then introduce the prospective buyer to him. Afterwards, if the buyer and seller get together on a deal, you will happily make $20,000 in commissions (2% of the selling price). This introduction can be made in person, email or by mail. These opportunities do exit and it is possible for you to find hundreds of these by checking the classified sections of the major business papers and local papers.
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