Apart from options (and futures), I would advise against everything. The fees (especially spread) are often far too high and in the case of special events the providers often simply do not quote prices (this should actually be criminal). Most strategies don't work with warrants / KOs anyway. The only advantage is that the offsetting of losses for private individuals is not limited as with options. However, this is only thanks to the banking lobby, which is happy to continue making easy money with warrants and certificates. Trading in all derivatives doesn't really make sense for most people anyway, as the vast majority are already very well priced.
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@Clermit agree with you, fees are high and the simplicity of execution with neobrokers is also more of a problem, but the fact that no strategy works with it is not true, it's just not as promising as it could be with options.
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