Multiple rating models on potential assessment

Summary

Can potential assessment contain more than one rating model

Content

I am preparing for our yearly talent review process and have received a new requirement this year for the potential assessment. The requirement is for some questions to have a 3 point scale and other questions to have a 4 point scale. The additional scale item would be a (N/A) due to the fact that these questions would not be applicable to all people in the assessment. 

I do not think I can use 2 rating models on the potential assessment so my thought was to just use the 4 point scale on the entire assessment with the (N/A) . Does anyone else have a similar requirement they have worked with and have suggestions?