Build me a portal for 8 people to use

We need a portal to post updates on the sale of 3 commercial properties and monthly updates on profit and loss ON these three properties until they are sold. There is also a 4th category involving a refund which should be closed out by late Dec. On the log in side would be 6 people (family) on the admin side would be a fiduciary and a lawyer (sister). Each building would the same 6-8 data points that could be updated by either admin person on a weekly basis. The PnL info on the 3 buildings would be 3 separate PDF documents that would be uploaded by the fiduciary once a month for a total period of no longer than 12 mos or end of 2022. This is to allow family members to track the liquidation of estate assets and what stage they are at. Not particular on where to host and I may even have some space on my Zona account as this is a temporary portal. All we need is a URL and then generate some log in and passwords. Would like to have the fiduciary email link accessible in the portal if there are questions. I would also like a "notes" section on each category so the fiduciary can add any more detail . The goal of this project is to avoid having to schedule and attend ZOOM calls to update the beneficiaries as to what is going on. If the 6 want to know what is happening with the sale of building X.....they log into the portal. I would provide the data points.