With a simple BP/W and DGX or Deep6 regs, you can get set up with equipment that will take you all the way to advanced technical diving for a fraction of the cost of retail recreational dive equipment from an LDS. You'll have equipment that is bullet proof, modular, and easily configurable, with simple to replace, generic parts in the unlikely case you need to switch something out. Mailing regs out for service to DGX is actually faster for me than driving (twice) to an LDS. And if you decide to someday learn to service your own, service kits are readily available.
I've been steered poorly more than once by LDS's not out of bad faith but just out of ignorance. That being said, I need them for air fills and want them to stay in business, so I do try to buy ancillary equipment and consumables from them, even if it costs more than online.
Also, on the rent vs buy debate, there is something to be said for the familiarity that comes with having your own equipment. When you put on your own BP, you know where every buckle and ring is, and you don't have to make any adjustments. And with your own computer, you can play around with it at home until you're much more familiar with it than you would ever be with a rental.