I usually don't see a lot of Cowboy Bebop cels go
for any less than $100, especially Spike.  That
cel might go for $150-200 if you are lucky since
it is a unique and humorous looking cel.  
As far as framing, I have no idea, but like the
others said it all depends on how much detail was
put into it and if it was done professionally or
not.  Most people who put cels in frames make SURE
they get UV Protectant glass and Acid Free paper,
otherwise, you might unintentionally damage the cel.