>   <xsl:template match="RentAmount | MonthlyAmounts">
>     <xsl:attribute name="class" select="'money'"/>

This will no doubt go down a long road but... that dangling attribute
creation there is a bad idea, as it depends on that template always
being executed directly after a start element is added to the result
tree.

Should something change where the last thing added to the result tree
was a text node, or closing element, that attribute call would cause
an exception.

-- 
Andrew Welch
http://andrewjwelch.com