Allah does not love the squanderers

Then he continued, 
"Do you think it proper that a person purchases from the wealth which Allah has entrusted him, a horse costing 10,000 dirhams when he could have bought an animal worth 20 dirhams?; and it would have sufficed for him. Or if he purchase a slave-girl at a cost of a thousand dirhams when he could have got one in twenty dinars and quite sufficient for him? When the Almighty says, 
'Do not spend wastefully.' 
(One who wastes and squanders money has done Khayanat in the trust of Allah). 
(Mustadrakul Wasael)

Abbasi says that he asked Imam Reza (a.s.) as to how much he should spend on his family? Imam (a.s.) replied,
"Between the two which are disliked."

I said, "I don't know what those two are?"
"Certainly Allah hates extravagance and He hates miserliness."

Imam (a.s.) then recited the ayat, 
"And (the people are) those who are neither extravagant nor miserly. They are the moderate (people)." 
(Wasaelush Shia)

Imam Ja'far as-Sadiq (a.s.) has said that if a person is extravagant and later becomes poor due to it, his invocations will not be accepted. Then if he says "O Allah grant me health," Allah (a.j.) says, "Had I not ordered you moderation?" 

The meaning of extravagance and its types

Extravagance means crossing the limits or spending wastefully. It depends upon circumstances. For example, spending on something useless is Haraam, even if it is only a single dirham. Spending unduly even for a proper ocassion is extravagance. If a dress of one hundred rupees is good enough one should not purchase a dress costing five hundred. According to certain scholars spending at the wrong place is squandering and spending more than necessary is extravagance.

Hazrat Ali (a.s.) says, 
"The extravagant have three qualities; he eats more than required, he wears more than is suitable for him and buys things needlessly." 
(Behaarul Anwaar)

Imam Ja'far as-Sadiq (a.s.) says: 
"If you wear a formal dress where it is not required, it is extravagance." 
(Mustadrakul Wasael)