What do you take when demoing new gear?

I gotta say this, don't get mad. We use to DEMO buildings.. LOL
Destroy them.. words count.. I mean DEMO.  Then build a new one!!
There was a lot of sound involved for about 1 minute.. Yup..

Not even one song worth.. Demo!

OP, I asked some stores to do some weird stuff, most will actually do it..
I drug in a speaker (center), a stool, I use for proper height, (it goes everywhere), GOOD camera,  tape measure and  my SPL mic is on my phone.. The stool doubles for a Mic stand  I feel like Jerry Lewis in  "The nutty professor".  It gets me some serious looks, but it works.. I have a test CD, tones and music. The chair back at one meter is a constant for measurements and an 8 x 8 x 8 or 10 x 10 x 10 triangle.. for some testing.. and the chair back..

I found a LOT of the sensitivity data way over stated. 

No more than a tote bag and a tripod folding chair, with a back and pockets. Less the speaker, that was a one off..

OP it's your money, just ask...BIG grins help too

Regards

Wallet

CD and LPs.

My ears and my common sense and an idea of what I want and as much information as I can find about it beforehand. 

I usually just bring source material.  However, if I find something I'm interested in, I will attempt to borrow the piece of equipment over a weekend, or whatever period the dealer is comfortable with.

Nothing beats an audition in my own listening room.