Bon Marche means "A good deal" in French.
bonbon (in one word) means candy in French.
a sweet
C'est vraiment bon marché means 'this is really cheap / affordable' in English.
bonfire (one word) is a contraction of "bone fire" -- referring to an ancient Celtic practice of burning the bones of ancestors. These days it refers to large outdoor fires, usually built and burned...
the weather is fine, the temperature is agreeable