It is hard to earn enough to cover insurance, fees, updates, new training materials, DEMA, and clearly 100% instructor-related stuff. But when you throw in something like dive travel and additional equipment, it is REALLY hard. You might not be able to claim all your diving expenses and still show a profit. Luckily, many of my purchases are really to support my recreational and tech/cave hobby, so they don't get claimed against the business side of things. Travel is harder: you go on a liveaboard or to someplace like Bonaire, do some dives with some students and some recreational dives too....how do you approportion your trip costs, when the dives were maybe 25% of them professional and 75% recreational? My accountant (you DO have one of those, don't you?) is happy for me to use those percentages and prorate any of my expenses that are supporting both the pro and the fun diving. The key is to report that you made money 3 out of 5 years (that is ANY consecutive 5 years...so you can't make money in years 1-3 of years 1-5 and then lose money in years 6-7 of years 6-10, because that is 4 years in a row (4-5-6-7) of losing money) and don't try and cheat.