Read the following article, note it references a fairly cheap autopilot for light General Aviation aircraft, review the unit prices, then consider it still has to be installed by a certified avionics technician and flight certified. So double the selling price, or more. Understand this is just the autopilot, not anything else related to the aircraft.
If you want full scale accuracy you will have to pay a lot higher price for a multirotor.
TruTrak autopilot STC’d for Skyhawks, Cardinals - AOPA
Garmin's latest autopilot releases are a little more expensive;
"That more limited level of testing is partially responsible for the pricing difference between the GFC 500 and 600. The 500 base price of $6,995 is little more than a third of the price of the 600, which starts at $19,995."
If you want full scale accuracy you will have to pay a lot higher price for a multirotor.
TruTrak autopilot STC’d for Skyhawks, Cardinals - AOPA
Garmin's latest autopilot releases are a little more expensive;
"That more limited level of testing is partially responsible for the pricing difference between the GFC 500 and 600. The 500 base price of $6,995 is little more than a third of the price of the 600, which starts at $19,995."