Hello, I am having a bit of a problem here.

Problem: I have to do a billboard design for a client and it seems that nothing I do as far as scaling will work for me to get the desired or proper sizing for the project and export.
And now I'm not even sure where to scale it to.



Project Purpose: Billboard sized at 48ft wide x 14 ft high.



Attempts:
I tried scaling the project at 1inch = 1ft in the scaling tab so I can see what I am doing on my page because If you don't change this, you won't be able to see what you're doing.
When I export the design at 300 dpi and put the pixel amount into a converter to check the footage size, it comes out waaayyyyy off. Not even big enough for an actual billboard
which wound up confusing me.

Sometimes it even changes the dpi to 28 dpi without me even asking it to. This is so frustrating. I thought this would be easier to do.



Tool used: I used justintools dot com to check it.




Advice:

1. What am I missing here? what step am I missing?

2. Does anyone know how to use this scaling tab in the Utilities > Options tab?
How should I scale it?

3. Does anyone know how to do Large Format design in Xara? because it seems that it's done differently than in Illustrator.





Thanks in advance