Childproof cabinet locks
We found that the safety locks that have a magnetic key for opening work the best.
Fencing
This is an absolute must. Some tips are to get an 8-12 foot privacy fence. Typically the flat face side of the privacy fence is facing out. If your purpose is for the safety of a family member that is severe on the spectrum you will want the flat side facing into your property so that the family member does not use the cross support as an aid to climb it. If you have a concern about digging under or over then something like chicken wire added on as diagrammed can solve that.
BioMetric Locks
A key for every door gets to be extremely annoying. BioMetric locks that can recognize a fingerprint and open is easier to manage when there is an uncooperative child in the other hand.
Door Alarms
One on every exterior door is useful, but be sure they each sound different so you know which direction to run in.
Water Cut off Valves
My son has flooded a couple of homes. Installing water cut off valves to the bathtub and other water sources can save you from a big headache. I would recommend that these be put in a convenient place, concealed, lockable. If they are not convenient then they will not always be used.
Sinks that auto shutoff
My Son has fluctuated my Water consumption from 4800 Gallons in a Month to 24400 Gallons. Getting those Bathroom Sink Faucets you find in an office building where they shut them selves off will more than pay for itself.
Gates
Baby Gates are useful but after a Child with Autism is able to push past you're in trouble. Having Dutch doors, or wooden gates that are the same size as a baby gate but hinged and heavier will help greatly.
Odor out enzymes
Some children with Autism, Experience CVS (Cyclical Vomiting Syndrome) or they take far longer to potty train. If you can get rid of all Carpeting you will be better off, but if you cannot then they make Odor-Out Enzymes that help manage extreme cleaning jobs.
Also consider different flooring options: Tile, Stained And or Sealed Concrete
WebCams
An InfraRed webcam in our son's room helps us see if we really need to go in and take action or if he is just fitting. You know if you open the door to check then the child will be awake regardless of what Schrodinger may have led you to believe.