Assuming you are asking about drum roasting, if you have never roast before, Diedrich in Sandpoint, Idaho, Ambex, and other roaster manufacturers offer seminar that will give you some ideas if roasting is for you. Roasting is not hard to learn, but it takes effort and dedication to be a decent roaster, never mind a master roaster. Without a doubt roasting adds additional complexities to your operation. But if you can roast better than average beans, the positives are that your cost of beans is lower, your beans are more fresh, and all things being equal your customers will think your shop is more quality oriented. The negative are that if you cannot deliver on the perceived quality, i.e. your coffee taste no better than the shop down the street, then it's a waste of your money and your time. Oh, did I mention roaster fire? Ultimately, it all depends on your level of expertise. If you have plenty of experience running a coffeehouse, then it's up to you if you want to take the next step.