Understand health insurance coverage
Autism is expensive. Very expensive. Everything costs a fortune because it's specialized. Many practitioners don't even accept insurance. Few sources of funding exist, and the ones there are, are generally overwhelmed. You will need to learn how to use your insurance and other sources of funding BEFORE using your own money, or you will be bankrupt fast and you won't be able to access the help your child needs, long term.
Learn who SHOULD be paying for a treatment, therapy or service before you pay. Who Pays for What?! - A Guide to Services, Providers and Payors
Even if a doctor or provider says the don't accept insurance, you may be able to get it covered or (partially or all) reimbursed.
Even with insurance, there are tips to save more money on Medical, Medical Travel, Diet, Public Assistance programs, and the diet on public assistance. There are also a number of community grants available.