I guess you live in the states, then.

An absolutely standard question when you take out insurance.

Alec

After reading this I couldn't remember if this was a standard app question
or not (since most of my line specific work was for home owners, I work as
a programmer for an insurance company) so I asked one of the other
programmers that worked on Auto.  It is pretty standard here in the US.  So
my next question was what did it mean.  The answer is has there been any
modifications that would increase the value of the car (so if you total it
the replacement would be the same).  So we pondered the question of how
much modification would be what you would need to put down. (The joy of
working as a programmer is that you must also become an underwriter)  Our
opinion (and note it is only our opinion) is that you should list a
modification if should the car be totaled, you would want the cost of the
modification to be considered for your replacement, or if the modification
significantly is a departure from the car's design or the mod changes the
cars capabilities.  That is to say if you are putting in an engine that is
nothing like the ones that was put in it at the factory, or a suspension
that causes the car to do things not intended at the factory (like causing
it to "jack" up and down or putting an off road suspension on a Porsche).
So if you were to put a 928's motor in a 924, then you should report it.  A
1000hp race motor, then report it.  But a 4 cyl. engine in a car that had a
4 cyl engine and they are both the same, or damn close to the same cubes,
and you don't care to get paid for it if it gets stolen, then don't.
Contrary to what most believe your liability is not really affected by the
car you are driving, only the comprehensive premium.  I spend significantly
more to insure my 2003 full size van then my brand new SUV, and gobs more
than my 924.  But all of them are the same for personal liability. That is
more to do with the drivers record.

HTH
Paul.