I put together an example here:
https://public.getgrist.com/1gasmnhKjQdN/Tenant-Ledger-3959/m/fork
The page “Tables” shows all the sample data. The page “Quarter Dashboard” shows a list of tenants – it’s just the list of companies filtered by Type of Tenant. Linked to that is a summary of the Ledger table, grouped by Company, Quarter. So it shows the selected tenant’s sums per quarter. Just below that is the list of transactions for that tenant for that quarter.
I didn’t have to use the type of the company in the Ledger table here, because the selection is by company. But if you needed to use that, you can, as @hera suggested: in the Ledger table, ensure that Company is of type Reference to Companies; then add a formula column with the formula $Company.Type (I think @hera’s answer has a typo there).
To get quarters, I used the recipe from Recipe for getting Months and Quarters from dates, but AI Formula Assistant does a great a job of it too 
If I misunderstood, or if something isn’t working, a screenshot could help understand what you are trying to get to.