Your vet would be the best one to answer those questions.  What do you mean
"options to put her to sleep"?  Generally it is an injection given in the
vein, the pet goes to sleep and peacefully passes on.  It is painless and
humane.  Depending on the vet and your wishes, you may chose to be present
(I used to work for a vet who did not want owners present, but I have found
that is not the norm, most will allow you to be present if you wish).

Options available for after wards, there used to be mass burials, which I
think they have gotten away from.  Now most places cremate the remains.
Again, you have a choice of "mass" cremation, meaning a your pet is done
with others, or "private" cremation where you can have your pet's remains
back.

Costs - it differs from vet to vet.  Cremation and burials generally go by
weight.  To have my one cat put to sleep and cremated it cost me $54 - that
included a brief office call in the price as well.  Cremation for my last
cat was $27.  That was only for cremation.  Again, only a vet in your area
can give you specifics.

I am sorry your cat is not doing well.

JoJo

Euthanasia is done by injecting a drug into one of the cat's vein.
Other than possibly starting an IV to get an access point, it's almost
completely painless of the cat and very quick.  When I put my cat to
sleep last November, they gave him a sedative to relax him prior to
starting the IV, as he went down fighting.

Most vets will let you stay with your animal until the end, then give
you some privacy afterwards for the grieving process.  I wouldn't have
it any other way - I, at least, needed closure.  I stayed with him the
entire time, trying to comfort him, until the end.  I probably cried
for ten minutes afterwards.

The vet office handled all the arrangements after that.  I explicity
stated that he was not to be sent for any anatomy dissections (having
dissected cats in an anatomy lab), and was assured he would be
cremated.

As for cost, it varies greatly.  The entire procedure only cost me
$10, but that was at a military veterinarian clinic so it was
significantly less than a civilian equivalent.

My Vet doesn't charge for euthenizing or cremation.
He believes it's bad enough you are losing a pet.

If the animal is very bad off and he can't find a vein, he gives
it a sedative so it won't feel anything when the time
comes.

My last cat was like that (FeLeuk) so he sedated her. And
10 minutes later he injected her directly into her heart. She was
gone in nanoseconds.  I held her the entire time.

I will never leave an animal alone at the vet to be put down
anymore.  It kills me to have to be there, but I want the last
voice they hear to be mine, telling them how much I love them.

LT