I would estimate about a week, and that's working at it!  I can also
safely say, a "pro" that rebuilds a player in three days, has not
restored the valves!

Here is a handy tip I learned from Larry Broadmoore.  Don't look at the
player action as top and bottom units.  Break it down: do the valves, do
all the bellows cleanup/sanding at the same time, the pumpers, strikers,
the air motor, all of them.  Keep clear notes of the span and anything
else.  Do similar operations of the entire unit all at once.  If you
rehinge, rehinge every board in the piano at one time.  Recover
pneumatics at one time, all of them.

At first I thought Larry was a bit odd, approaching a player like this.
But with time, I learned it sped up the work, I would guess by about a
third.  For this to work, you must have all components numbered and a
"map" of the job(s) to do for the day.  Always number the parts where
they won't show after the unit is reassembled.

But a side note here.  We tend to get more detailed in our work, the
more players we do, so take that in consideration as well.

Andy Taylor,
Tempola Music Rolls