In my high school years and college years I was partying and doing drugs instead of focusing on my future.

If you stop and think about the disasters caused by doctors actually prescribing unneeded drugs or performing unnecessary surgeries, you'll realize they're taking no risks. 

They find all the cash on me & the assumption is drugs.

Drug house down the next block (you're violating the zoning man!).

Some definitely do, which alleviates the risk.

Drug addicts go from being homeless street urchins to tee totaling Bible thumpers who scold people for having an occasional beer.  

It will scratch if furniture it drug and not lifted.

Get a Crime Free / Drug Free Addendum and make them all sign it..

They receive a receipt for their records, thus alleviating any payment discrepancies.

Take GRAPE jelly ( only Grape for whatever reason ) and mix in a small amount of the powder boric acid ( safe and available everywhere including dollar stores, drug stores, home centers etc ) put small amounts of it out on disposable plastic lid containers or such and place them in your home where you see the most ants.