Allow for multiple companies (subsidiaries), and for consolidated accounting
This is a variation of another user's suggestion, except it does not address variable reporting periods among the various companies. I believe this is therefore a simpler feature case.
The user creates a single chart of accounts, but for each transaction, create an additional column of data: the company.
Then, for reports, have a check box which presents: a) all transactions, b) only transactions for company 'n'. For example, if the user creates 2 companies, three reports are possible, "Company 1", "Company 2", and a consolidated report.
Post a transaction which impacts retained earnings?: the company column value would carry into the RE account. Similarly, for other events, like closing periods and etc.
Create a check box in the settings to allow for multiple companies. Create a dbf table for the companies with the company number, 'n', associated with it. If multiple companies are set, also enable a check box which will or will not provide a phrase after a single company notation, ie: "Chart of Accounts has other companies not represented in this print out"
Create a menu item, enabled when there are multiple companies, that either allows entries for all companies (user manually inputs the company 'n') or defaults all entries to be within some fixed 'n', or forces all entries to within "n". If multiple companies allowed, place menu setting in the title bar - ie, "Company N" or "All Companies" in addition to whatever else is there. If that menu item is set to a specific company, all actions (eg, reports and etc.) default to that company. The company scope could be changed, however, when actually running a report.
For reports and etc., if multiple companies are set, either say ALL COMPANIES at the top, or COMPANY N, with potential added phrase, noted above.
For reports, if ALL COMPANIES, either consolidate values for all companies for each account, or print individual account lines for each company. If printing segregated lines for each company, choose to print or not print an account total for all companies.
In chart of accounts, create settings on each account's definition which are available (or is used) if there are multiple companies: a) print account as consolidated or list out individual company's values; b) if listing individual companies also print account total also on additional line
My use case is fairly simple (definitely much simpler than the OP). I'm an independent contractor. I have a DBA (Doing Business As) name which I use for computer consulting, but I invoice under my own name for other work I do.
All I need is the ability to add multiple "profiles" under Files > Properties > Business, and to select from those profiles when printing an invoice.
Many small business owners dabble in multiple businesses. Also people who own rental property have multiple entities. Being able to have separate accounting for all of them, in one set of books would be very useful. This would make transferring funds from one to another easier, It would make reporting easier, and it would make budgeting easier.
It would also be good to have the ability to have different ownership structures for different companies. Say you own 20% of one company and 100% of another. Then 20% of the profit and loss for the one company will hit your tax return and 100% of the other will.
Julien Meunier commented
Too bad this suggestion is not merged with "Be able to have multiple companies with independent accounting periods" ... this is lowering our vote towards parent / children company accounting