Help tracking the cost of hotel room nights

Hello, 

I  am trying to track the cost of hotel room nights in one hotel and I have a second table tied to it via the Invoice # field to report to an invoice.

The people who are traveling are traveling for multiple invoice cycles at a time​. I have the week total column adding 7 fields that I have to manually change the formula to change the dates. And the invoice #  column reflects the full line.

Here are my questions:

Is there a way to make dynamic fields (columns) that are date dependent and can be automated to add to the sheet each week? ​

How can I continue to use the week total column and Invoice # without creating new entries each week?

Can I move the past columns that have been invoiced to a different table?

Any  other suggestions or examples of how to build this better?

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Thanks,
Tara​
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