Work really doesn't scale linearly with servers with this type of business. I've known my current tenants for quite some time and they aren't "needy" or problem users, which makes my job easier.

I'd also either need to purchase a new cabinet or move into a cage -- which is not really an upfront cost (or the headache of contract negotiations) I want to take on for a hobby business. In either case, I'd have to start running my own switches (and god forbid router) and while I roughly know how to administer both, those are better left until I have more time to devote.

On the flip side, I have toyed with racking up a few 6U blade servers (~50 blades total) and renting those out as unmanaged, 0-support servers. The problem here is its a race to the bottom with blades and I'm no Softlayer or OVH and can't buy these things at hefty discount. I have worked out the math and after the first 3months, if I sell at least 60% of the blades I'll be paid off and the margins are significantly higher than my current servers.