We have two standards :-)

The normal one is the semicolon count. However, this seems to us to be
misleading especially when preparing for Fagan inspections, where
there's an external "standard" for the number of lines you can
properly do in one inspection (about 250, IIRC). For that purpose, we

  eliminate comments
  eliminate blank lines
  count the lines left.

I have to say that there's an extremely strong correlation between
measurements using the two schemes, with some outliers.

You certainly should count declarations, they can be a high proportion
of the work. Not so sure about withs, but why not go with it and
adjust the ratios slightly.

I don't think I would be popular if I told you what our figures are,
but I can say we'd normally work on a figure for the whole process
(requirements through to factory acceptance, say). So what you pay the
contractors must depend on how much of this they're doing.