This is a children’s series
Boy lives in lighthouse with an AI companion who designs all-terrain ships/vehicles. Boy uses advanced technology mods to fight elemental monsters. There was a secret base underneath, and the main character fights elemental monsters that occur beyond the borders of human habitation. the areas are separated into the prime elements such as water, earth, air and fire along with mixed elements such as mud and lava.
My son was reading this at school in 2010/2011 and waiting for new publications at this time. He has confirmed that it is not ’The Edge’ series or ‘Monsters of the Earth’.
Might these be the Mac Park series? ‘Aquatan’ Is the first of his Battle of the Worlds books.
I just looked them up and showed him he is thrilled. Yes these are the ones he was looking for. Thank You Sharyn
https://www.fantasticfiction.com/p/mac-park/