$300, plus or minus $50, depending on condition.
$450-$700 Depending on date of Manufacture and Condition.
50- 275 usd
AMT Automag II's are going for $450-$600 in good condition.
You need to ask an actual question here before it can be answered. What did you want to know about it?
100-500 USD
There were three models of the AMT (Arcadia Machine and Tool Co) Automag II .22 magnum pistol. You do not specify which of three barrel lengths you have or the condition. The original AMT automag II in good condition is currently selling for $300 to $440. The High Standard Company has taken over manufacturing the Automag II. See the link below. The current MSRP is $695.00. The price in 1988 from AMT, about the time your gun was made, was $325.00 This particular gun is prone to jaming due to the gas locked system, and rough 12 hole gas system, and cannot use certain ammunition factory loaded with ball powder. Anyway, that is probably more information than you wanted.
S&W never made an automag.
No longer in production (AMT was sold) values would depend on condition, but roughly $500-$700 for Excellent specimens. The 9mm magnum is a very scarce cartridge, "demand" is about non-existent except among collectors.
About $600.
25-125 USD or so
50-125 or so
75-200 USD depending on condition.