Gasto (past tense). Gasta could also work because he could be saying that she spends a lot at the clothing store in general, but it is Gasto.
not a peep means don't talk
Explanation:
so sancho spoke by saying not a peep and bolsa Is speaking by saying not a peep so as there are telling each other not to speak they are speaking
These are correct :
Él no va nunca a la iglesia. (second option)
Tomás no dice nada. (The first option)