Hi Will. No advice here regarding location, but what type do you have in mind? Our boat has MarineAire reverse cycle heat pumps that use sea water to heat/cool the boat. Expensive, but very efficient. If you're looking for a regular portable air conditioner several models to choose from. It would help if you provide a bit more detail as to the type or style you want. There are some that operate on 12V DC, which helps while on the hook someplace and still keep the boat cooler than the outside temps. Either way, electricity demand for such a device to operate factors into which type you select.