question charity flight

Hey, I'm you basic 200hr PPL-ASEL and a friend
of mine has asked me to donate a sightseeing
flight to her charity's auction.

Four questions:

First, since I'm not being reimbursed for the
flight, I don't even think this fall under
61.113(d). It's basically just me taking up
a stranger where, no money changes hands, at
least into my hands. Is this correct?

Two, if it is a charitable flight under 61.113(d),
do I need some sort of form or paperwork. The
charity has some kind of 501(c)(3) tax exempt
letter they can give me.

Three, I'm not getting reimbured, but can I
deduct my rental cost from my taxes?

Four, I take friends with me on trips all the
time, but usually after telling them all about
the potential risks, including that I'm a
relatively inexperienced pilot, but with
strangers, this feels a little different.
Anyone have opinions?

thanks,
-- Dave Jacobowitz
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