I'm the type of person who would rather buy something that's expensive once rather than buy a bunch of cheap things.
この場合、次のような言い方ができますよ。
ーI'm the type of person who would rather buy something that's expensive once rather than buy a bunch of cheap things.
「私は安いものをたくさん買うより、高価なものを一度買いたいタイプです」
I'm the type of person who ... で「私は…なタイプです」と言えます。
ご参考まで!