You repair a car to maintain the means of transportation not invest in it. If a car has been well maintained it may be worth repairing even though the fair market value of the repaired vehicle is low. New cars lose more value in depreciation during the first few years. Consider buying a pre owned vehicle. Avoid going into debt to make a purchase.
Installment debt is expensive.
Try to save for major purchases. Use coupons for grocery purchases and take advantage of sales. Do not use the coupons and sales as an excuse to buy something you do not want. Thrift shops selling used clothes and furniture can be an excellent source of fulfilling needs at bargain prices. They are often run by charitable organizations, hence buying goods from them has socially redeeming benefits as well as opportunities to save money.