TBF nothing is going to prevent a dent, or scratches, without PPF, even then dubious.
I guess we need to know the car to be protected and budget to do so before proper recommendation.
Really depends on what you want to do.
A professional polish, and ceramic coating with something like gtechniq could cost from £850.00 to £1500.00.
Something like cquartz uk, (a very good ceramic and easy to apply, even I've done it) which could be applied outside if temperature is within...
Whether Biss is world class or not is a matter of opinion.
For me he's not, yet!
But he is a top 6 player, so sadly possibly too good for us at this stage in his journey.