Is there a maximum dollar amount of spousal maintenance or is it based on many other factors?

Spousal support depends on many factors.  The amount of spousal support is determined by the lifestyle to which your spouse has been accustomed.  There are many factors which determine the duration of spousal support and whether or not spousal support is even ordered.  In CA, the following factors are considered in determining spousal support: the extent to which the earning capacity of each party is sufficient to maintain the standard of living established during the marriage.  Factors considered include: marketable skills of the supported party; job market for those skills; time and expenses required to obtain the education and training to develop those skills  and possible need for retraining or education to acquire other more marketable skills or employment; extent to which supported party's present or future earning capacity is impaired by periods of unemployment during marriage due to domestic duties; extent to which supported party contributed to education, training, license or career position of the supporting party; ability to pay of the supporting party considering earning capacity, earned and unearned income, assets and standard of living; needs of each party based on the standard of living established during marriage; obligations and assets; duration of marriage.  Death or remarriage terminates spousal support.  Spousal support can be for a fixed period of time or a contingent period of time.  A vocational training consultant can assess a party's ability to obtain employment based on age, health, marketable skills, employment history and the current availability of employment opportunities.

As I mentioned, these are factors that are considered in CA in determining the amount and duration of spousal support.  Your state may have different rules, but this is just to provide some general background information regarding spousal support.