السَّلاَمُ عَلَيْكُمْ Is there extravagance (Israaf) in buying fragrances? If I do not have an income but have money saved up, and nobody is dependent upon me, how much of my savings can I spend on fragrances if I am buying natural, expensive fragrance rather than a large number of synthetic ones?

Spend according to what you're capable of spending. If you are not capable or it causes you difficulty, then don't buy fragrances at all, or just buy one thing that you can afford; that would be enough. Also, consider your financial capabilities. Once Allah subhanahu wa ta'ala bestows upon you and you have a good income, you can expand in that which you like.