I think you're looking for this:

ggplot(df, aes(y=name, x=value, fill = cost)) +
  coord_cartesian(clip = "off") +
  geom_bar(position = "stack", stat = "identity") +
  geom_text(
    aes(label = after_stat(x), group = name), 
    stat = 'summary', fun = sum, hjust = -0.5
  )