How many weeks, months, years until you're willing to or don't mind paying for stuff for her.
Ex. Replacing her phone if she broke it or if it was stolen.
Paying to get her car fixed (battery, oil, tire change)
Paying for a cd or something or going clothes shopping
Paying for hair
Food, dates, vacations
Putting money into her hobbies, activities, classes
Education
A puppy
A car
Apartment/house (for the both of you)
Each circumstance is different. Examples.
1)Food, Dates, and flowers can be paid for early on in a relationship ( I usually pay for the date anyway). So it's whatever ( weeks-early months in relationship)
2)Stuff like paying for hair, clothing, shopping can happen after two or three months.
3)Bigger things like car, education ( I may make an exception depending on the urgency), phones can be handled after I'm sure we are serious ( 5-6 months).
4) Apartment is when I'm confident we're getting married ( 10-12 months)