Do not go for 110v power tools. Tools won't be able to deliver complete power if the converter is not good. Also a converter is generally bulky and it will be a headache to move it around when polishing around the car.
If you plan to detail professionally, then go for Rupes DA. I prefer 21 mm throw as it has more torque. Due to long throw it is challenging to use on certain curves and tight areaa and requires good technique.
If you just plan to be a weekend warrior then go with low cost chinese DAs. Vertool DAS21 is very good. liquidelements also has good DAs.
If you have any other questions just PM me.