Hi Stephen
No to DVLA as its not classed as a permanent colour change – However I know it is prudent to talk to your insurance company as it may be classed as a modification, or they may want to charge an additional premium as it would add additional cost to repairs if damaged.
Regarding how far you go depends on how much time/money you want to spend on it. Covering all elements including sills, door inners etc well add a lot of time and some of these areas are quite complex as well …. also depends on how different the original paint colour will be to the new wrap to how much it would show or stand out on opening the doors/boot etc.
If you’ve never wrapped a full vehicle before then i would advise you either bring in a specialist wrapper or invest in a decent wrap course and be prepared to redo a number of times before you’ve mastered the art ….. quite different fully wrapping a car than normal vehicle or sign graphic application.
Finally you may want to consider a paint protection film instead of a full wrap if you’re actually just wanting to protect the paintwork. Standard PVC films will protect only very minor abrasions but any stones etc will still break down a wrap. Paint protection film being much thicker and Urethane rather than PVC will protect most that will be thrown up by a dirt track …. other than hitting a tree/wall or other vehicle 🙂
Hope this helps
Stuart