1.    I arrived home late - as usual.  (1 dash)
2.    Fido (Sam's smelly dog) was barking loudly.  (2 brackets)
3.    Sam stood there - fixed to the spot - wide-eyed with fear.  (1 hyphen, 2 dashes) 
4.    Outside was a loosely-tied rope-ladder.  (2 hyphens)
5.    Some light-fingered thief had come in (no surprise to me) and stolen all the silver.  (2 brackets, 1 hyphen)
6.    Fido - the supposed guard-dog - had failed again.  (1 hyphen, 2 dashes)
7.    He will have to go.  I know I won't be able to do it.