Well, I'll get offers on my cels now and then.  
Usually I won't let them go, since now my gallery 
is full of all my favorite cels that will be 
getting framed after AX =).  

But, if I am ever in a pinch in the future I'll 
take offers on my cels.  I keep a record of 
everone who's sent me offers in on my cels, & 
before posting up a "For Offers" message, I will 
e-mail them & notify them that I'll accept an 
offer on the cel they were interested in 
earlier.  I always have in mind what I want to 
get for the cel.  I won't take less than what I 
paid(Unless the market for that cel has dropped 
below my original cost), & I won't take an insane 
amount over what I paid *UNLESS* the market for 
them at the time deviates otherwise. I'll allow 
them to be first to make an offer.  If their 
offer isn't what I'm hoping to get I'll kindly 
decline them, & go from there.  If they decide to 
make another offer that is more of what I'm 
looking for, then they get the cel, otherwise 
I'll put it up for everyone else to have a stab 
at.  If I get an offer higher than the "Dib" then 
it will THEN go to the highest bidder.

I always keep the "Dibs" person in the run too, 
as well as everyone else.  It's only fair.

Hope this provides some helpful advice ^^'!