Dennis Marury, author of all of the Adventure Helpers hint books recalls:

Wow... I had forgotten how many I had! I used to slave over making the maps, using only a ruler and a rectangle cutout. I made them so the full solution would not be immediately revealed, giving them hints first. I just had the idea to make hint books, and went from there. I didn't even know how to make a booklet or how I could print on both sides of a page. Spent a lot of time at the Hackensack, NJ copy shop. Remember, this was before high-powered computers, printers, etc. I put a display ad in Electronic Games magazine for about $700. I got a decent response, but it was way too expensive to advertise in there again. So, I placed simpler, smaller ads in various mags. I got up early every morning for this "job" and went to bed late. Never made much money, but I loved every minute of it. I did manage to get into the Lexington Ave., NYC Software City, as well as 3 more of their locations in NJ and Long Island. Sold pretty well.