My uncle is very wealthy, but rather parsimonious in his habits.

Parsimonious : very unwilling to spend money or use resources.
Extravagant : lacking restraint in spending money or using resources.
Generous ; showing a readiness to give more of something, especially money, than is strictly necessary or expected.
Careless : not giving sufficient attention or thought to avoiding harm or errors.
Strict : demanding that rules concerning behaviour are obeyed and observed.

Antonym of Parsimonious is Extravagant