I'm the compliance oversight officer for a national IFA. @Elphame yeah I know exactly what company that is too!
Commission was replaced by fees in 2013, the only "commission" to be earned now is from protection policies. All advisers charge a fee for their professional services, as an accountant or solicitor does, although IFA's rarely charge hourly.
It's simple really, if you think you know best and all advisers are out to shaft you, invest it how you see fit. If you're not sure of the long term tax implications, indications for capital growth or loss and how investment risk works, use a professional and pay them for their expertise (there's been some good points made about the illiquidity and fragility of property investment already).
There is a minimum level of qualifications and evidence of ongoing development required of all proper advisers, and all the dinosaurs who used to take the highest amounts of commission for the least amount of work have all but died out.
I'm not denying that there are charlatans, swindlers and rip-off merchants out there, but it's easy to tell - if it sounds too good to be true it probably is. Any promises of performance are false or exaggerated, and if anyone tries to rush you they're probably shite. Check the FCA register for their firm, an investment adviser must be authorised and certified. Don't invest in anything "sexy" like bamboo or teak, carbon credits, Film Schemes or Dubai car parks. 🙄 Don't take more risk than you can afford to lose, which might mean sticking it in a bank account.
There is nothing wrong with advisers recommending their own proposition at all (certain places, let's call them St Jimmy's shall we, charge a hefty fee and tie you in to a minimum contract with exit penalties but it's only them that do that) - everyone else does much the same thing. They are still classed as independent because they will have conducted complex research to decide what platform and investment approach they'll use for their proposition (and repeat the research every year), and if it isn't suitable for you they'll come up with an alternative. It just means they're not tied to a provider or investment house.
The problem with financial advice these days is that the regulator tied up all the rules so tightly that there is now an advice gap - it's not worth advisers getting involved in the process and taking on a client for less than £100k, and anyone with less than that doesn't really want to pay a fee.