Can you put a Krell in an apartment?

I’m sensing you going against all instincts here and getting the amp... I’ve done that before too. Makes for a longer road (and $$) than expected to get where you're ultimately meant to be. 

Krell will service the amp for 1500 bucks. If I buy It at 3500 I will be in it 5 grand. Do you think any 5 grand amp new will be as good?

I don't know about the specifics of this amp, but, something that old that cost so much back then would be astronomically higher in price in today's market.  I doubt that there have been much technological advances in amp design that this amp would be easily outperformed at this price level.  Of course this is all contingent on the amp being in flawless condition. 

All Krells run hot, and heat always shortens the life of components.  If this has been a heavily used amp, it might not be worth the price of purchase and refurbishing.  There really is no way of knowing, so it is a bit of a gamble.  It is good to hear that Krell can still service the amp, that is not always the case with old solid state gear.

Jeff,  I don’t believe you will hear a difference in weather or not you have a 20amp breaker or 15 amp unless you’re running full tilt maximum output, which I doubt it if you in an apartment. The only way the breaker will come into play is if you suck more power that it can handle and it will trip the breaker. Now,  that being said if you have a dedicated line for the amp with nothing from the rest of the apt on it,  then that will sound cleaner due to isolation tho no the breaker size. As far as harming the amp:  well I have be running a Krell 300c on a regular 15 amp line for years with no issues but I don’t play my music at ear shattering levels.  My amp was built in the late 1990s and is working fine to this day. It does run run a little warm being class A however I like the Class A sound. I’m sure there are many amps out there that will sound a bit better but I’m pretty happy with this one for now. If you’re really concerned I’d call Krell.  

I really like the dynamics and rock solid deep bass of these amps. Could the be a little smoother? Sure, but I like them. Remember this is a D’AGOSTINO design and still a respected product. Buy one of his current amps and see what that will set you back. Lol!  Enjoy!