score:4
There is good discussion in this article, this article and this article. You can read those for much advice.
For canonical advice:
The Sigalovada Sutta states:
The wise endowed with virtue Shine forth like a burning fire, Gathering wealth as bees do honey And heaping it up like an ant hill. Once wealth is accumulated, Family and household life may follow. By dividing wealth into four parts, True friendships are bound; One part should be enjoyed; Two parts invested in business; And the fourth set aside Against future misfortunes."
The Dighajanu Sutta states:
"And what does it mean to maintain one's livelihood in tune? There is the case where a lay person, knowing the income and outflow of his wealth, maintains a livelihood in tune, neither a spendthrift nor a penny-pincher, [thinking], 'Thus will my income exceed my outflow, and my outflow will not exceed my income.' Just as when a weigher or his apprentice, when holding the scales, knows, 'It has tipped down so much or has tipped up so much,' in the same way, the lay person, knowing the income and outflow of his wealth, maintains a livelihood in tune, neither a spendthrift nor a penny-pincher, [thinking], 'Thus will my income exceed my outflow, and my outflow will not exceed my income.'
"These are the four drains on one's store of wealth: debauchery in sex; debauchery in drink; debauchery in gambling; and evil friendship, evil companionship, evil camaraderie. Just as if there were a great reservoir with four inlets and four drains, and a man were to close the inlets and open the drains, and the sky were not to pour down proper showers, the depletion of that great reservoir could be expected, not its increase.
The Adiya Sutta discusses the 5 benefits obtained from one's wealth. The fifth is charity.
And don't forget that income should come from Right Livelihood, as stated in the Vanijja Sutta:
"Monks, a lay follower should not engage in five types of business. Which five? Business in weapons, business in human beings, business in meat, business in intoxicants, and business in poison.