Yes... 3 LETTER or 3 NUMBER dot com (dot commons really) are in the thousands.
3 CHARACTER (mixed numbers and letters) dot coms are in the lower $xxx.
However, they are coming up rapidly. I've been keeping a log of every 3 character dot com sold for the past month and the average is over $250 per domain with several reaching toward $1000.
It depends on the 3 characters.
v7q.com probably is worth $130 - $150
x1x.com is getting bids of over $900 right now
F1R.com has been appraised at nearly $3000
Look and see what's behind the 3 characters and price accordingly.