If it helps, Desie, I believe there is some worth in a visual, especially in the situation you describe. (That is, buying a property)
Whilst no actual tests will be carried out, an electrician can tell a lot from looking. (How many sparks carry out a full PIR before quoting for a rewire?) For instance:
Approximate age
Presence of additions/modifications
Serviceability of accessories (sockets, switches, etc)
Adequacy of protective measures - earthing, bonding, CPCs etc
General non-compliances, obvious to a spark but not to a surveyor.
In fact your description of a visual inspection is very much in line with what I would expect.
By the way, if you do let out the property you would be foolish to do so without full and satisfactory test results. But that's further down the line.
A lot of electricians grumble about 'nothing less than a full PIR will do' but I disagree. In the future I believe that visual inspections will become very popular as additional information for buyers. As some have found out, most punters don't want to fork over the cost of a PIR, especially if it comes back 'unsatisfactory'.
And as a spark, why not put your name to a visual report? After all you are still employing your expertise and the limitations of the inspection should be clearly stated. So, on principle you'd prefer to get no inspection work at all? Or would you rather supply a perfectly reasonable market demand?
Because one thing's for sure, if experienced electricians refuse to do less than full PIRs, yet surveyors recommend visual-only inspections, you can bet your life that less-qualified people will quickly fill the demand. Who wins then?