This is a valuation for the lenders benefit. In some cases you may not even see a copy of the report and is designed to establish whether the property is deemed as good collateral to lend against. If there any issues the lender may recommend a further survey or inspections before they can proceed with a mortgage. In some cases the lender may charge a fee for this survey but this will vary depending on the lender.
This type of valuation is for the benefit of the buyer. The report will inform you of any major defects and will advise if further inspections may be needed. The report will also assess if the purchase price agreed is deemed to be suitable to help you to make an informed choice before you proceed. Unlike the basic survey if the survey or surveyor turns out to be negligent or you are dissatisfied you may have some recourse in terms of making a complaint or getting the property re-assessed. The buyer will generally cover all of the costs of this survey.
A building survey is the most detailed survey option and is highly advisable for unusual, listed or older (pre 1900) buildings. This survey covers all aspects and can take a few hours to complete. You have full recourse with this option and you can expect detailed advice on areas such as woodworm and damp that may arise. This is the most expensive option and the buyer will cover all the costs.