I am opening my business and one thing I was thinking about making large quantities of my buttercream, then just warming and whipping it up when I needed to frost the cupcakes. This would help a lot. How long does buttercream last in the fridge? I am planning on using real butter in my buttercream.

How about cream cheese frosting?

Do you think this would work or would I be better off making it fresh each day? I'm just trying to think of ways to save time. Thank you!

Buttercream will last about 2 weeks.
I'm not sure about cream cheese.
And it depends on how many cakes you are planning to do each day.