They work on a flat fee or commission basis; it is up to you to decide how you want to pay. They can be independent or work within an investment company but each advisor will be responsible for particular files or portfolio. In a mutual fund company they would be responsible for investing the money in the portfolio in a way to arrive at the objectives of the investor.
Banks also have what they call investment advisors but how independent can they be when they are paid by the bank and banks.
Investment advisors are financial experts and insider knowledge of the financial world that puts them in a position to advise others. Financial knowledge may be public knowledge but a trained eye will look at it differently and offer a different interpretation. With insider knowledge and experience investment advisors may be able to point their clients in the right direction before loosing money or to make money.
They will scour company financial reports, watch stock exchange indexes, network and keep an ear to the ground on the latest rumours from the financial world and anything else legal in between.
Investment advisors cannot work miracles. The financial world regulates itself and is influenced by environmental and political factors. An environmental disaster can mean big losses in an industry that was all the rage yesterday; it does not mean your advisor was wrong in telling you to invest in yesterday. For example, a fire or flood can mean loses in the building industry but relief can come from rebuilding. Changes in government laws like taxation can also bring negative or positive changes. It all depends on which side of the fence you are standing on and whether you are ready to change.
You cannot easily blame your financial advisor for failure to make a return on investment unless of course he deliberately misrepresented information to you or made an unsuitable investment decision on your behalf. You will have to file a complaint against the advisor with the relevant regulating body in your area. You will have to prove that indeed the advisor was wrong. They have been many cases of financial advisors plain stealing from clients. Some set themselves up as advisors yet they do not have a real experience or knowledge in the field that is a good recipe for a disaster. It is important to check the background of an advisor before you engage them.
Of course you could try to go it alone, do the research on your own and with the many online tools available invest your money; at least you will have only yourself to blame. So many are doing it already, be prepared to understand and interpret financial reports and act on them.