I don't say there aren't risks in housesitting, except to be ironic or gain attention for a rhetorical point. The biggest risk is the house might hatch while you're sitting on it. It would be cute witnessing the Really Quotidian Miracle of house birth, but if you don't dodge pretty fast the house chick is liable to imprint upon you. Sure that's initially cute, but do you want a townhouse nuzzling your heels as you do things like driving to work or wondering if the doughnuts in the convenience store shelf are created faintly stale? Or if you get into abnormal activities like staring back at pigeons? Even a small colonial will scare all but the most aggressive of pigeons, so you're left staring at sidewalk while foundations scrape your heels. Worse is if something goes wrong in trying to un-imprint it, leaving you convinced you're a house, resulting in angry calls from some title insurance company.
But housesitting for a friend can be a great way to spend a week in a vaguely sad resemblance to the vacation your friend is taking without you. There's the sense of adventure coming from staying somewhere the neighbors don't know you, where you don't know where the convenience store with ponderable doughnuts is, and where the shower is not as comfortable as the one you have at home. It also lets you buy fresh shampoo because you forgot to take your old bottles with you, and then buy new bottles again because you leave the new bottles behind accidentally when you leave and the old ones you'd left are empty anyway. Also you have the chance to carefully study what DVDs your friend has deliberately selected to own, letting you question what you ever actually had in common with this friend. Plus there's the chance to get lost on your daily commute.
Housesitting for an enemy has different but not identical perils. There's the risk of being charged for breaking and/or entering. And if you start when your enemy hasn't left there's liable to be fights over who sleeps in the master bedroom. The superpowers you and your enemy have affect things, too, and there's the chance of a continent-shattering explosion if you go after one another too urgently before showering. If neither of you have superpowers just set up a schedule about who gets to use the pre-dampened shower already. You can leave the continent alone in that case, unless you're the person supposed to be sitting it, in which case you probably want to be gigantic anyway. That's technically a superpower so you don't need instruction on handling non-superpowered sitting.
The most important part of housesitting is the paperwork. Every day you should measure the house's interesting properties such as its water use, food consumption, interior volume, and number of bicycles found inexplicably hidden behind the hedges that none of the neighbors admit to owning. Chart them on a daily basis, and then plot seven-day moving averages. If it turns out that the volume of the house is steadily decreasing over time this will let you know when you'll have to move out: it should be at latest before when the house becomes smaller than you. Report all this data back to the person you're housesitting for so that your friend won't be worried about coming home to find the house has four fewer rooms. Plus by sending enough data you can get revenge for the DVD collection.
If you're also petsitting as well as housesitting first check whether there are any pets to sit. Then also be careful that you're only metaphorical in petsitting. You actually want to stand off to the side and near the pet, because they get over twenty percent less pleasant when sat on. They too can be shown the paperwork about the house's condition, and letting them scratch or nibble on the edges is a great way to add authenticity and prove you were there. If you weren't there, perhaps it was a house that thought it was you. If the sat pet's house hatches while you sit that, I don't know, something must make sense.
Trivia: Souvenir penknives sold in France in 1919, engraved with ``Foch'' and ``La Victoire'', were made in Germany. Source: Paris 1919: Six Months That Changed The World, Margaret Macmillan.
Currently Reading: Bananas: How The United Fruit Company Shaped The World, Peter Chapman. Oh, you British authors: The label on each bunch [ of bananas, in his childhood ] said `Fyffes'. I mistakenly took this to be a `British' company --- one of those that were all around us like Woolworth's and Ford. But at that time Fyffes was part of the United Fruit Company.
Also I just realized The Wonderful Writing Machine despite being a history of typewriters doesn't mention Dvorak at all. Weird.