Here is my walkthrough of the Drug Czar challenge.
I won the computer guru challenge by being honest, but this one wouldn't budge. First, you
will start out with lots of cash and factories producing, fruit snacks, chocolate bars,
yogurt, and ice cream. Set the timer thing to zero so no time passes, and go from city to
city and snatch up every resource. Spend the money. Place a $200,000 mansion right beside
the resource and no one can use it. When you want to start mining, demolish the mansion
and sell the land. Don't crank the prices too high or your customers may go out of
business. Don't kill the goose that lays the golden eggs for you.
Now, eventually you are going to have to add cakes, cookies, and chewing gum to your
product list. I forgot chewing gum. Don't do it yet. Now, go to your stores, check your
prices against your competitors, and make sure all your sales units are linked to your ad
unit. Some things are messed up. Cakes and cookies have a hard time selling in distant
cities, because the cost is high to export them. Don't make duplicate factories. You will
go bankrupt. Place your prodcts and then lowball the price until they just begin to sell
(you'll see the red "demand" bar). Make up the difference with a small price increase in
one or two commodities. Play it by ear. Keep going to your stores and factories and
checking on things. I kept running out of strawberries and wheat.
Don't forget timber as a commodity. It will sell eventually. The commodities take time for
demand to develop. They won't all sell at first. I took coal and iron ore and produced
steel. Keep checking your cities for new commodities to snatch up. They will keep
appearing. They even show up in the middle of downtown!
Don't build R&D or a Corporate headquarters. Waste of money. You build value with training
(turn up the training on everything). Now, when you have $50 million or so in profit,
start building stores in other cities. Go slow. You will need two or three per city, but
it takes time. Then add your factories for gum, cookies and cakes. I used my own farms and
set everything to "internal sale". When you are buying your own coal,for instance put the
price down for your factory. It will boost profits.
Then, when you have $200 million or so in profit, go to every store and set the price of
everything to 1 cent. Boost profits by adjusting commodities prices. It will work.
Eventually you will take command of market share of everything. If you are having trouble
(chocolate bars) build a convenience store (cheapest) and sell  nothing but chocolate bars
in it.
Keep checking your competitors prices and quality. Often you can adjust  your own prices
upwards. You do this in the store menu. At the top click on the picture of the item. A
screen will show you the competitors quality and price in that city for that item. Then
decide.