thank you for your kind comments !, the secret is in base prep, the better it is the better anything else you put on will look, claying, having a smooth swirl free surface, removing polishing oils so sealant bonds perfectly all are very important, for you car, you would already know for removing swirls ultimate compound, either by hand or DA, keep at it with practice you'll be cutting like a pro, invest in a good car cover to keep the car dust free, theres really no other way then to give a rinse free wipe, remove all clothes and only keeps micro fibre in cloths, there are dry california duster i think they are called available for dry dusting, maybe your father car try those if he has to clean using a cloth,
you don't need to use a detailer spray everyday if you want it just for protection, however i use detailer spray to clean the car if there is light dust everyday instead of rinsfree, and mine also has carnauba so i am constantly building layers, there is no harm in using it everyday, but it benefits can vary depending on use and which one you got,
for fully restoring your paint, avoid cleaner waxes or all in one products, go for full, clay-compound-polish/glaze-tough prep (if your polish has polishing oils instead of water or acrylic based)-sealant/wax keep a low hand on the compound if you can't ensure no scratches later though
so keep at it eventually you'll get there!