The sensible answer is that if you are serious about purchasing any property, you should have it surveyed by a RICS chartered surveyor. A building survey will give you an expert opinion on the condition of a property and identify any structural or other issues.
The advantage of having a survey done is that you will know what the property is worth and if it is worth making an offer on.
The disadvantage is you might spend several hundred pounds only not to bid at all - in that case, however, you may have saved yourself thousands in the long run.
When you are buying at auction with a mortgage, your lender is also likely to demand more than simply a valuation report on an auction property. This is because they need to be certain the property is worth what they are lending to you in case of default. Talk to your property auction solicitor about your survey options.