Very clean, quiet, and little (like Tokyo little) apartment that's not too far (roughly 1 mile) from Ikebukuro station where you can pick up the Yamanote line. Even closer to Higashi-Ikebukuro station to get on the metro, but remember that JR passes aren't valid for metro trains. Finding the apartment is easy also thanks to some helpful instructions from the host.
Soap, shampoo, cups, microwave, and pretty much anything you'd need for your average stay is available. There's also a small market nearby where you can pick up anything else.
A few restaurants nearby but not too many and you'll need to catch a train to get to most major destinations, but it's quiet, affordable, and there was never a crowd.