Hi miroflex,
Glad to know that you are exploring all options. However, unless the used-equipment-dealer is well known and is recommended by a lot of members of the forum who have had direct interaction with the dealer, I would advise you not to consider this option.
...Look out for sales by audiophiles. Here also, in general one needs to be careful so that there is no bitter feeling later on...
...I know some people have got good deals this way from boom-a-rang in Bombay and Sridhar (ARN Systems) from Bangalore. I am sure there are other dealers who help out their existing customers this way and at the same time get in new customers. To me, this seems a fair procedure, and helps out all three parties.
Regards.