A professional adviser should be paid by the client for the service that is offered and no monies should be taken from third parties as inducements to sell their products. If any income is received, it should be rebated back to the client or used to offset any fees that may be chargeable.
If a wealth manager is positioning themselves as the trusted and impartial adviser to advise and manage a client's wealth, they are potentially compromised in their impartiality if they are also manufacturing products to sell to the same clients.
Arguably, it is perfectly acceptable for a wealth adviser to sell products made by the firm they work for. The adviser just needs to make it clear to the client that they are not impartial and that they are limited to selling and advising on the products of their employer and they are remunerated by the product provider with all costs suitably disclosed.
A partnership approach is necessary in building a long term client relationship, where the adviser provides a service that they truly believe is good and is value for money. The client can then decide whether they trust the advice and whether they perceive it to be value for money. If and when the adviser makes a mistake, they should admit it, apologise and ensure the mistake is remedied as soon as possible.
In an increasingly complex world, either avoid the products that you cannot understand or figure out how they can deliver what they are promising. The adviser should invest with conviction in areas that they believe in and avoid those that they do not have conviction about merely to be in line with a benchmark.
A good adviser will always know when they are at the end of their knowledge and skill base. Unfortunately too many are too afraid or proud to admit that they don't know the answer. A good client will never hold it against their adviser if they don't know the answer to a question but they will if they think or find out the adviser didn't know and had simply made up an answer.