So far there are claims that these paintings are by three different C Inness':
Clara D - doubtful as she was considered to be a fine artist and these are certainly more "Bob Ross" than fine art.
Colin - doesn't appear to have existed except here (no records of shows or awards, no record of RAF service, no census data, nothing)
Carl - a delightful, undated, story accompanies one of these paintings, of a rather elderly Carl Inness living in Tuscany and is assisted by his adopted son.
These are likely factory paintings. They're formulaic, the signatures change, some have been duplicated, and NONE have any provenance. They are available and owned all around the world.
I'm surprised at the original answer.