This will depend on the woman. What does she expect? What will she be happy with?
You can give the same allowance to three different women, and you would likely get three very different reactions. One might never be happy or satisfied with what she gets and will always want, expect or demand more. A second may be at least be satisfied with what she is getting, and the third may be very, very appreciative and even thankful for what she is getting from you.
Some women think their shit does not stink and a man OWES them just to look at them, let alone spread her legs for you.
Some women are not so assholistic, (I think I may have coined a word:) and at least be satisfied that she is receiving some help from you.
And one woman might really need the the extra help that you can provide her. Maybe she had to work three jobs, and by seeing you she cut that down to two, or even one.
One women may look at a SD that doesn’t provide a luxury lifestyle, and a $5000 allowance as a Splenda Daddy, and another would look at an extra $1500 per month as a Sugar Daddy.
I would look for a women who appreciates what I can do for her.