I'd do it. For $400 bucks and some elbow grease, that's a steal.
Getting to the Apple logo is a good thing in terms of the other hardware in my experience - at least you know the screen, RAM, CPU, etc seems fine (probably). It could be just some drive corruption.
so i just bought it, the condition overall is 7.5/10 just because its close to 5 years old...everything worked however. i was pleased....so the problem was that after the hitting the power button it would chime, apple logo would appear, the spinning wheel appeared but then it would STOP it froze...i took it to the apple store he ran some tests everything checked out fine except for some sort of corruption on the HDD (understandable) he tried a series of key holding diagnostics and NOTHING...he told me i had to switch out the hdd it was faulty. lol i took it home i referred to the guides above and i fixed it...it was weird i boot it into safe mode went into disk utilities and repaired disk permissions. viola fixed...my risk was a reward.