I install a/c Fgas registered etc. In my view there are 3 types of a/c which could be used in this scenario. 1- Portable unit as mentioned, hot air is vented outside... a little noisy for a bedroom me thinks, would need to cool the room prior to going to bed and then turn it off.
2. Split unit for DIY install, these look like a regular split unit with seperate outdoor and indoor unit and have most of the facilities, the pipes are all pre-charged and you just make the connections similar to connecting an airline. You need some skill to install and tools to drill a hole circa 65mm through the wall and mount the outdoor unit to something substantial like a wall or solid base. You are limited to the pipe work that comes with the unit and if there is too much you have to hide the excess somewhere
3. Split, professionally installed. These, legally, must be installed by a Fgas installer. Pipework is bespoke to the install and additional gas may need to be added. The pipework is pressure tested with N , first to ensure there are no leaks, then the pipework is vacuumed to -1bar for a good period, this removes all air and moisture from the pipework to ensure top performation from the unit, then the gas is released into the pipework. MI's always state this method.
Hope this helps