I've been browsing around, checking out different leasing companies and came across Leo Palace today.
Is anybody familiar with them? From what I've been able to gather, they tend to rent smaller places (not really "palaces") and give decent discounts if you pay for a longer stretch up front. They don't do the key money thing and all utilities are included - power, water, internet...
Doesn't look like too bad of a deal, depending on where they've got places, and might come in handy if the "end to key money" rule gets ignored by all the lessors in Tokyo.