I used an 8,000 BTU portable A/C unit for Irma. Portables are horribly inefficient, but it did the job if that is your only option. 8,000 rated will produce only around 4,000 actual of cooling(they actually state it on their required labels). It worked, kept a small single room in the 70's, while also running the fridge on a 2200 watt HF generator at about 4 gallons a day of fuel. Since they use conditioned air to cool their coils and then exhaust that air, they actually pull hot humid air into the rest of the home. That's what destroys their efficiency.
I since have purchased a small window unit for backup A/C. It will pull almost 1 amp less, and produce 10,000 true BTUs of cooling, while actually reducing the overall house humidity. For a temporary use, it is not really any more difficult than a portable unit to throw in a window. Easy choice for 2.5x the cooling, drier air, and using less fuel/power. Plus, no need to camp out in the small office vs. a larger room.