[xsl] Complex Sorting Help

["Crist, Trevor" <tcrist@xxxxxxxxxxxx>]

In the following example, I am trying to return the Property with the cheapest
TOTAL rate first.
What I WANT to do is something like, this, but of course it doesn't work...
Any ideas how to get the desired results?

XML:
<Properties>
	<Property Name="My Hotel">
 		<Room Name="King Room">
			<Day Date="04/15/2006" Quantity="2" Price="180.00"/>
			<Day Date="04/15/2006" Quantity="2" Price="180.00"/>
			<Day Date="04/15/2006" Quantity="2" Price="100.00"/>
		</Room>
		<Room Name="Suite">
			<Day Date="04/15/2006" Quantity="2" Price="280.00"/>
			<Day Date="04/15/2006" Quantity="2" Price="280.00"/>
			<Day Date="04/15/2006" Quantity="2" Price="240.00"/>
            </Room>
	</Property>
	<Property Name="Other Hotel">
            <Room Name="Queen Room">
			<Day Date="04/15/2006" Quantity="2" Price="150.00"/>
			<Day Date="04/15/2006" Quantity="2" Price="165.00"/>
			<Day Date="04/15/2006" Quantity="2" Price="165.00"/>
            </Room>
	</Property>
</Properties>



XSL:
<xsl:for-each select="Property">
<xsl:sort order="ascending" data-type="number"
select="Room/sum(Day/@Price)"/>
       <br/><br/>
       <xsl:value-of select="@Name"/> <br/>

       <xsl:for-each select="Room">
                   &#160; <xsl:value-of select="@Name"/> :
			<xsl:value-of select="sum(Day/@Price)"/>
       </xsl:for-each>
</xsl:for-each>



DESIRED RESULTS:
My Hotel
 King Room: 460.00
 Suite: 800.00

Your Hotel
 Queen Room: 480.00