there are 2 schools of thoughts of this.
those who can not live with themselves if they had not "tutored" their child
and
those who think it should not be needed. i.e. it was meant to be or not meant to be.
my own view is that tutoring is a big waste of money...hard cash payment...as some like to receive it as (don't tell hmrc!). i think it is better use to burn the money than to hand it over to a tutor who feeds on our fear of failure to get our lovely DC into schools like NLCS.
but then, if parents had not use a "tutor" and DC failed to get in, then parents would blame themselves.
however, looking at the rejected candidates and those who were accepted, something stands out with the girls who got in. they all have that extra special characteristic (sparkle) that makes them stand out of the crowd. the quiet shy type should not apply.
in hindsight, i wish my daughter was at a "normal" non-elite private school.
why? i am not in fintech, finance, medical or law field and I did not attend oxbridge/LSE/imperial like most of the other parents.
I would rather mingle with "normal" (i.e. humble) parents. those that know what is a pint of milk or a loaf of bread. knows how the other 95% of the UK population lives.
so my own advice. do not pay anyone hard cash notes to have your child tutor. follow the advice given by other mums on what to teach your child 12-24 months before the assessment date. i.e. colouring/finger grip/scissors/jigsaws/playdates/social interaction with other kids/etc
if your daughter does not get into NLCS, it could be a blessing in disguise. like FanDabbyFloozy said if they can not keep up they will have to leave, but will end up with a happier child and less stressful life for the whole family. good luck and give the NLCS assessment your best shot!