Congratulations on the new bundles of joy!  You are in for a real treat!
 
As for your questions, I don't know that a children's playpen would be
too god for them.  It may not be the biting that will cause the problems,
but it will be the digging.  Some ferrets (not all) that are confined
will try to dig their way out of places.  With the mesh on the side of
children's playpens, the ferrets will be out in no time, regardless if
plastic mesh.  You can try it, but you will need to watch them at all
times if you don't want them to come out.  I have personally never tried
it, but this information is based upon observation of other ferret
parents!
 
As for the ear cleaning, we scruff ours.  My husband and I tag team the
ferrets, as we have 11.  He scruffs them and I clean the ears.  That is
the best way to get them to hold still.  Keep in mind that they will
still squirm, but just be careful.  Don't jam the Q-tip in their ear.
Use a ear cleaning solution for ferrets, squirt a couple drops in , rub
their ear, and then just clean the area that you can see.  Once you put
them down, they will shake their head and the liquid will come out,
possibly with other gunk.  Just watch the color of the ear wax.  If it
close to a black color, they may have ear mites.  Ferrets are notorious
for ear mites.
 
In regards to clipping nails, scruff them also.  When you scruff a ferret
(or cat also) it releases chemicals that make the ferret relax.  Now,
they don't relax all the time, but most of the time.  Once they get used
to being scruffed, they won't give you many problems.  You will read that
most people recommend putting Ferrettone on their belly or on a surface
for them to lick as it preoccupies them so you can clip each nail.  I
find that dangerous.  The ferret can move, slip, or whatever, and BAM!
You've clipped the quick and the ferret bleeds profusely.  You can't
focus on the quick as well as you can when a ferret is scruffed.  The
ferret can move when scruffed, but you will know when it will happen
better since you have control over them.  Again, it takes two people.
Some may do it by themselves, but again I find that dangerous.  I have
been clipping ferret nails this way for years, and never hit the vein.
Whereas, I have heard of many stories of people doing it the other way
and making the ferrets bleed.  Just have styptic powder (or baking soda)
available just in case.  Once you do it a few times, you will be able to
breeze right through it!
 
After ear cleaning, give them a treat.  After nail trimming, give them
a treat.  Ours don't mind the procedures at all, because they know the
reward afterwards!  We always do it in our kitchen, and when we are out
there, they all gather out there waiting for something to happen.  We
have one who will lay down on his back as if waiting to be scruffed.
This is the only room in the house that they ALL congregate on one time.
They sure are smart
 
Just some helpful suggestions for one who has been doing this for years.
 
-Angela and her gangster mob of 11 fuzzbutts.
[Posted in FML issue 4771]