I just watched this SpaceRip video on YouTube which shows pictures taken by Hubble while looking into the disk of the Andromeda galaxy to study a certain type of variable star. It occurred to me that if we can study individual stars in Andromeda, we must be able to use most of our methods of exoplanet detection on them.
Is this true? If so, why not look for exoplanets in another galaxy? My logic tells me that since it's difficult to look through the disk of our own galaxy (since we're inside it), we're limited to a relatively local region for detecting exoplanets. But if we turned our sights to Andromeda, couldn't we study the differences in planet formation between different regions of a galaxy?
I also suspect that the reason we're not doing this is because we would need much more sensitive instruments for this, and because we already have one planet finding telescope in space (so it'd be tough to justify sending up another one).
Am I mostly right in this reasoning? Are we capable of searching for exoplanets in Andromeda? Would there be a benefit to doing it (besides the obvious cool factor)? Is cost pretty much the only limiting factor?