When you set the path to your build script, just set it so its like:
Solution\Service\bin\%environment%
Which will do it relatively to the build directory for your build agent.
Otherwise I think its:
%teamcity.build.checkoutDir%\Solution\Service\bin\%environment%
Which TeamCity will fill in %teamcity.build.checkoutDir%
with like C:\TeamCity\buildAgent\work\94fc00f485df5f29