Have a yearly “review” right before school year. Raise allowance as appropriate. If they want more money, they’ll have to take on more responsibilities.
IMPORTANT: If you borrow money from someone pay it back as soon as possible. In full. If you borrow an item, return it in excellent condition. I’d say if you borrow a car, return it with a full tank of gas but hopefully by the time you’re driving there won’t be any combustible engines. So return it fully charged!
Failed?
Lift yourself up, or live there.
You know the work you need to do, be it physical, mental, emotional or spiritual, etc. So do it. Do the work.
The only bitterness in failure comes from not having the guts to get back up again.
Beware that when you’re first exposed to a new thing: a car, a college tour, house, etc. you will feel AMAZING and totally seduced by the shiny newness. Be cool. Remember that glitters is not gold. Things don’t need to be perfect and even if the house is it doesn’t mean life will be.
Check out from the library or Amazon: “My First Money Book: A Guide for Parents and Children to Saving, Spending, Sharing, and Investing Your Money” by Reggie Nelson
Misquoting someone here: “It’s not about getting everything you want, it’s about giving everything you have.” Stuff will never satisfy. Pouring yourself into something heart and soul will.
Practice “going without.” Talk about how nobody gets what they want all the time. We should learn how to just choose to go without something we want. Get them in on the discussion and pick something every day to do without.
Take the family on periodic “spending fasts.”
As an exercise, go a day, a weekend or a week without spending any money. Make due with what you have.
Encourage participation. Tie in spending fasts with holidays, lent or in support of a cause.
"Watch the pennies and the dollars will take care of themselves." - Ben Franklin
This works with money and with other areas: Be faithful in the little things and the bigger things will take care of themselves. For example, if you don't get comfortable with telling little lies then you'll never tell big lies.
Start “home economics” school with them. Laundry, cleaning, cooking, how to change a diaper, comfort a baby, soothe a toddler, what's involved in caring for pets, budgeting for food, keeping track of maintenance schedules for humans, pets, cars and machines. Engage with guests, be a good host, etc. Know when and how to tell someone to GTFO of the house (racist or misogynistic speech, etc.) Every kid needs to learn the art and science of home management. Look for and point out examples in books and movies of good home science skills.