Well, it cost me approximately 20.00 to do three cats. If the infestation is
light, oil might work for a while but mites are pernicious. It would also
not keep them from reinfesting the ear from furniture the cat was on.

every

RobZip,
Of course, not everything is an emergency.  Some things can be treated at
home.
The OP did not say why she wanted a home remedy for ear mites. She did not
say how she knows the problem is ear mites and not something else.
We can assume that money (or lack thereof)could very well have something to
do with it.
However, treating ear mites is basic medical care. It should not be an
extraordinary expense.
Our pets depend wholly on us for whatever care, including food, water, and
medical that they need.  It is our responsibility to find some way to meet
at least those basic needs, not to look for excuses to make them do without.
Unless the OP is able to make an accurate diagnosis of ear mites, a home
remedy could make the problem worse if it is something else, not to mention
wasting money that could have been used for an effective treatment.
Doing the right thing (consulting with a vet in this case) can actually be
less expensive in the long run.
And, yes, I can remember taking the dog to the vet for a rabies shot and
making payments.  He let me do this because we had established a good
relationship by making sure the dog had the vaccinations and other care
needed, and the vet knew that we would find a way to pay him.  We figured we
owed it to our dog to give her the care she needed, regardless of our
personal financial situation.
Annie