Team Foundation Build Property for Build Folder
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Using TFS 2010 I need to build a solution that depends on a couple of other solutions held in different team projects. I'm editing my build definition and I create a list of "Projects to Build'. When it comes to build the parent solution I get an error because it's unable to reference assemblies created by the other solutions. So I go back to edit build definition and  add /p:ReferencePath="c:\builds\3\referencedproject\binaries\" to the "MSBuild Arguments" Build process parameters. 

Problem is, I don't want to hard code the c:\build\3. I guess there may be a $() property I can use in its place - can anyone please advise?