
Rosa.
If you feel you cannot devote time to the application, or if you circumstances are complicated or weak use an experience advisor.
The immigration advisor can clearly show how the immigration rules have been met and cross reference all the evidence.
There is a caveat though, no advisor can create a financial position that doesn't meet requirements, or create a level of accommodation that doesn't exist.
What I mean is that the basic evidence for visa application still needs to exist and be provided. Just that a good advisor should be capable to present the best case.
Having a advisor does not mean the granting of a visa is secured.