It could be from more occupied units in our building or the noise has gotten louder - I don't think is all that relevant.We are also not sue happy people but we also know that no one should have to hear elevator noise each and every time the machine is moving

Any renter loves to wash their own cloths at the comfort of their home, versus going to laundromat.  

However, I came into the office one morning, to my bare and boring cubicle devoid of any anime, action figures, posters, toys, and all the other trinkets techie guys are notorious for collecting and displaying, and sat down at my machine.

Of course, I could pull all of that equity and reinvest it into some other vehicle, but for purposes of some principal protection I would really just be exchanging one for the other, since the 3-6% earned in something fairly bulletproof would be little more than a wash from the marginal tax benefit subtracted from closing & interest costs.

If you didn't you can file Form 3115 to "catch-up" on missed depreciation and then it'd basically be a wash on depreciation: the tax credit and tax due would cancel each other out UNLESS your marginal tax rate is higher than the 25% recapture max in which case you'd get more tax credit than tax due. 

No portable dishwashers/washing machines + adding appliances without landlord's consent.

Will it earn enough to pay for itself, will I need a machine for each unit so I don't have the "Susan upstairs is hogging the machine on every weekend and she don't even work during the week" fights, etc.  

I took a 2/1 and made it a 5/3 and it's a cash making machine I've had the same group of college students in it for 3 years and it's not even trashed.

A power wash company could take care of that quickly.You might also be able to take it up with home adviser to deduct pay or fix it depending on what kind of guarantee they have.

You can bypass the 10k cap of State and local tax with house hacking.6)You can depreciate the rental portion of the house which can wash out most of the rental income that you otherwise had to pay taxes on.