Anything you can legally fly by hand can also be flown by the autopilot,
since
you remain in command and can take over at any time; using autopilot is like
using trim in that case. However, you can't use the autopilot to fly
something you could not legally fly by hand unless both you and the aircraft
are certificated to do so. As long as you are flying an approach that you
can
legally fly by hand, whether or not you actually use the autopilot to fly it
is purely your choice.

In the Cirrus the autopilot manual (STEC 55X) did not permit operation
below 200 feet or when full flaps were deployed. Clearly a case where
you could legally fly by hand but not with the autopilot.

The STEC 55X in the Cirrus SR-22 also had a prohibition against using it
with indicated airspeeds above 180kts, as I recall (I sold my Cirrus a
while ago but I recall that being the number). The same limitation was
not present for hand flying.
---
Ken Reed
M20M, N9124X

--
Ken Reed
M20M, N9124X