i think about that all the time
yeah ---- is there really a good patch that works outside?
I really try to caulk as much a possible -prime- wet rag, wet palm, or 5- in 0ne , you would be amazed - i would say caulks are actually better now than in the eighties.
But for the most part, I just use bondo. and they actually make a bondo for house repears, sands little easier. I usually start sanding as soon as i can- seams little ealier- alway have vacuum random hooked to vaccum- someday I will have a festool. bondo is cheap- I have had jobs where bondo last longer than rest of substates haha. things to keep in mind - vacuum bags. prime first if possible, vacuum, and get repairs done before fixing.
also there are tricks to tooling quad pro, or solar seal or demonic "butel based caulks, I do window casings to sill, got to be slick cause can stick out like sore thumb.
: they call me patch adams. " my grandpa use to say - if you can't caulk or paint it- it doesn't need to be fixed."