It is ideal to supply your own equipment, as you will finish the course with your dive gear optimally configured and ready to go. About 80% of students provide their own kit for sidemount and technical diving courses. Some prefer to invest in their own equipment ahead of a course and complete their training in their own kit. Others prefer to select and purchase equipment once they've completed training and know exactly what they want. It's not typically a problem to arrange for a supporting dive center to provide appropriate rental equipment - however, the benefit of conducting training with your own training is considerable. Many of the skills and practices in the sidemount and technical courses are aimed to develop equipment familiarity and ingrained responses. Obviously, if you subsequently dive using differently configured equipment, then you will have to 're-learn' or adapt what you have previously been taught. Recreational sidemount isn't a big investment in equipment. There are a number of commercial harness/BCD systems available to buy at approximately the same cost as a medium-high priced backmount BCD. Other than that, you'll just need an extra regulator 1st stage and be prepared to fit some different length hoses on. There is a distinct benefit in having your own sidemount equipment when you attend sidemount training; as the initial set-up, and sometimes modification, of the rig is the key foundation to diving sidemount effectively. Getting your own rig configured with the help of an expert eye will save you many hours, and less than optimal dives, doing it for yourself afterward. I am happy to consult with future students to help them select and configure their own sidemount rigs in preparation for training. This is part of my service. In contrast, technical diving is expensive - be under no illusions. If you are serious enough to make the necessary financial and time commitment to undertake technical-level training - then you certainly must be prepared to make a substantial investment in equipment also… either before, or after, your course. If you are considering the purchase of technical diving gear, please feel welcome to contact me for tips, advice, and guidance.  I don't sell equipment and I'm not on commission from manufacturers either - so don't fear a 'hard sell' approach or advice that may not be in your best interests. Having good quality technical diving equipment, that is suitable for your personal philosophy and diving preferences is a critical factor in successful training. I strive to teach excellent courses and create happy, safe divers - nothing more, nothing less.