For example: You suspect a house full of illegal aliens down the street from you: You hire a background checker who for $50/each scopes out whether they are citizens or on valid visas. You file a report on 20 of them for a filing fee of $100 each. The INS now has 20 business days to act or pay you a penalty of $250 per report. In 20 days they discover 17 out of 20 are illegals. You get $17,000 in reward money, net of $3000 in costs (keeps the bozos out o fthis business) you make $15,000 and that's probably a small fraction of the cost of building an INS investigation from the ground up.