marital resources.  Any money he gives is marital income.

"No" is a complete conversation. DH needs to learn to say no to his spawn.

No 14yo needs highlights or acrylic nails.  Even my high earning incredible bride does nails and gets regular admiration for her nail work.  No acrylics though. She pampers her claws and they are elegant, healthy, and her artistic efforts are exhaustive regarding her nails.  Don't ask how many bottles of nail goo reside in our home.

As for movie money.  Not an unreasonable request IMHO.  What movie can anyone see for $20? Tickets, corn, drink....   

Snazy new skips.... for a 13yo, that is on a need basis.  

I would give an allowance. Tie it to grades and behaviors.  She pays for anything and everything she wants out of her allowance other than true needs.  She also has to defend her cash from BM since invariably, BM will snake it.

Movies, nails, highlights, etc.... Allowance.  At 13 considering inflation I would say $50-$75 a month.  She runs out, she waits intil the next month.  At 16, mine was $5/wk. But that was 40+ years ago.  I was in boarding school so I had zero need to pay for anything. My allowance bought me a burger, fries, and a drink at the club room.

I am assuming that DH pays CS to BM, major things like hair cuts, clothes shopping, etc.... should be on BM's time as DH pays her to provide clothing and hygiene needs when SD is with mommy.   You and DH provide the roof and food when she is with you.

IMHO of course.

We tried an allowance for SS for a while. He never touched it.  He is not a big spender personality. He never has been. He was with us all of the time so movies, meals, haircuts, etc... we paid for.  He did have a big group of friends he socialized with in Middle School and HS (first two years). When they did group stuff, we gave him appropriate cash for that event.  We would take him and his crew for Sushi about once a month and pay for all of them.  Usually about 6 kids including SS.

Our kid was a mutuant. Generally very well behaved, low drama, and his friends were all band geeks (my bride and my kid are former band geeks as well) so the get togethers were always entertaining and with little drama.   Our drama with SS was grades and toxic influence of Spermidiot related.

I have no idea what young-ins get for allowance these days. I would keep it low as a lesson on budgeting and to teach kids that wants and needs are decidedly different things.

I think it's time for DAD to give his child an allowance and put her on notice that she needs to live within her means.  He can also set a clothing allowance.. and she can keep track of that with him.. to see if things are in the budget.

He should also give her the opportunity to earn more by doing extra work.. but he has to manage that.

She does sound spoiled... and I wouldn't have been allowed to have acrylics or fancy hair treatments as a minor.. I think those are within his right to say "no".

The other stuff.. movie or sneakers.. she wouldn't be the first to press for more.. or to get her sneakers "early".. a gift early.. and my parents were actually likely to give us things when we "needed" them vs some preset holiday.  I guess it depends on whether she needed new shoes.. or whether it was just a fashion "want".  

I do think she is old enough to start learning to budget though.. and to decide what is important to her.. prioritize and save.

I'm a big fan of allowances.  Set a certain amount, specify what it covers (clothing, grooming, entertainment or whatever) and, hardest part, don't bail her out when she's broke.  Mom did this with me and it's the fastest way for a kid to learn what's REALLY importent to them.

The second hardest part is watching the choices she makes

I'll leave it to the younger Steptalkers to suggest an appropriate amount nowadays.

Yes allowances!  Not that DH ever did that though. 

OSD always got what she wanted. Luckily she wasn't into the best clothes, shoes, nails and things, but she never had to lift a finger to get what she wanted and never understood the cost of things.

YSD is the opposite of a typical teen. She wants nothing. She asks for nothing. She doesn't see why she needs more than one pair of shoes, one sweater, a couple t-shirts, etc. Never does her hair or nails and uses no make up. I still think she knows nothing about money management because what she DOES need is special food for her vegan diet and DH never makes her shop for her special items either. We have a lot of the basics, but she can get the extras.

What I would say ....

"Um look here ... you want to dye your hair? Go to Walmart and get some boxed dye...you want movies? Pull up Netflix/Amazon Prime and select a movie/ I got extra large popcorn from dollar tree....you want your nails done? Grab some nail polish or some press ons...you want acrylics removed? I have acetone and foil in the pantry"

Don't like this? ----> Get a job!!!!

Total cost for having financial boundaries = $ 20 

Total cost for letting kids fleece you like daddy/mommy warbucks = $300

My own kid is like this. Champagne taste on a beer budget and constantly asking for money for things. I've had to set limits and explain that there isn't an unlimited supply of money and some things are just a "no." They will bleed you dry if you let them. Don't let them!