Too high a price to be on the level (5)
I believe the answer is:
steep
'level' is the definition.
Both the definition and answer are adjectives. Perhaps there's an association between them I don't understand?
'too high a price to be on the' is the wordplay.
'too high a price' becomes 'seep' (I can't explain this - if you can you should believe this answer much more).
'to be on' means one lot of letters goes inside another (as in clothing 'on' a person).
'the' becomes 't' (the is pronounced as a 't' sound in some dialects).
'seep' enclosing 't' is 'STEEP'.
Can you help me to learn more?
(Other definitions for steep that I've seen before include "Marinate" , "Rising sharply" , "Soak; expensive (price)" , "Sharply inclined" , "Without the bounds of moderation" .)