HMOs are the least expensive health insurance option, but
they are also very inflexible. They are usually used by groups that
seek health insurance, such as employment provided insurance.
HMOs offer low co-payments, very little paperwork and coverage
for most preventative-care programs. However, you usually are
required to choose a primary care physician, known as your PCP. You
are only allowed to see network doctors to receive coverage. If you
want to see a specialist, you will be required to have a referral
from your
PCP.