How much growth would you say a 14 year old girl with late puberty has left?

Depends: The growth potential of any kid is relative to their bone maturity. Late puberty is often paired with a bone maturity that follows the pubertal stage rather than age. A simple x-ray of the left hand can give a "bone age" & see if the growth centers show the kid has more time. I generally just tell parents a girl gets about 2.5 inches after her first period. Expected ht is parents ave less 2.5in.

Growth: The only way to tell is to have a "bone age x-ray " performed. This measures the maturity and closure of the growth plates. In girls bone age 14 means the plates appear fused or closed. A bone age younger means there is extra time to grow.