Do you buy gear new, used, both?

My primary system is mostly used except for the turntable, cartridge and all the cables. The HT 7.1.1 system is mostly new except for the subwoofer, center channel and front speakers. The third system is all new (old repurposed receiver, old CD player, old turntable with a new cartridge, and new KEF speakers). 

The primary system is mostly higher end stuff. The only way to justify purchasing it was with deep used, or demo discounts.

Both, but will go used if I find exactly what I'm looking for happens to be on the market.

Mainly new, a little used (tape deck), plus some DIY (wood cabinets, leveling platform, cable Y-sleeves).

Both here.  Demo gear is my favorite.  

Main system new and used...secondary systems mostly used and a few open box items...