@Keet

a Project Statistics plugin

is not a YAUP [:)]

#levels with #rooms (areas), #walls length and square meters per level/room/project,

I've already done with RoomsInformations plugin.
+ It calculate walls areas with and without holes.
For furniture I've used also the Calc (Excel) as Cristi did.
e.g. To know what amount of pipes (length/type) and connectors/type was needed to buy when I renovate my apartment.
Anyway could be useful to have something similar for furniture:
-the number of the same object per room/level and total amount (chairs, tables, beds ...).
Probably someone who's in need will do it.
I've finished my renovation and I don't intend to do it again (not in this life).
Wile I'm alive I'm available to help.