The first step in the loan approval process is receiving conditional approval. This means that the lender has taken an overview of the application and they are happy that you are able to service the loan with your income and they will give you full approval of your loan as long as some conditions can be met.
These conditions will always a satisfactory valuation of the property that you are seeking to purchase and may also include verification of the income that you are stating you earn in your job or from your investments.
Different lenders will have different policies as to the types of things that they require to be verified in an application – and they may sometimes ask for clarification about some of the things that you have stated.
Although a lender may approve the loan in principle, the loan may also need to be approved by the mortgage insurer.