Alcohol. Use it on the drones and remotes too. Makes them like new with no harm. Stronger the better. 90% rubbing is very good. I’ve used goof-off for markers and adhesives but careful to remove quickly. Turned many a used ugly ducks into swans. Looks sell.
Spray the props with car bug spray. These products dissolve bug splatter quickly. I even use it to soften tree sap from my chainsaws. I use a little 'Pledge' furniture polish spray on my props and on the body shell of my P4 to finish off. It gives a nice shine and a slick surface that resists bug splatter sticking too bad on your next flights.