i don't really know were to start or what to say so where go's nothing

Hi , my name is mike william and I'm a start up repair shop . i start doing repairs a few years back when iPhone 6 an 6s was a thong lols . now I'm starting to do motherboard repairs and still have a lot of learning to do . as far as tools . I've invested a few hundred dollars just over a thousand to be exact in just tools and now I'm in the process of finding schematic and board views on the web .. I've visited a few website looking for such but 90% of them don't have what I'm looking for or their asking you...