This is the area of much litigation.
Child support is a ‘hard guideline’ subject to a firm formula. The key in this area is making sure that the right numbers are used in these calculations. Where there are bonuses, or one person is self employed, determination of income may be difficult.
The basis of calculating temporary spousal support is much different than how permanent spousal support is determined. The public policy for each is much different, with temporary spousal support intended to preserve the status quo only, and permanent spousal support is designed to assist one party to maintain the same standard of living as they had during marriage, subject to the ability to pay and other issues.
Another fertile area of disputes is how long spousal support is paid. There is a rebuttable presumption for marriages of under 10 years in length that support will last for 1/2 the length of the marriage. This is NOT a hard and fast rule, and an area that you must get competant advice in.