On the same layout, I would also like to display a list of upcoming tasks. Now here's the catch: the chart and the list should be based on all the records that I would specify, not just the current.
And how would you specify those records? A date or date range? A task's category or department? or ?
You can set up a filtered portal to tasks and manipulate the filter to control what task records are listed if you have FileMaker 11. If you have an older version, you can still do this, but with less flexibility and you'll have to add a relationship that uses additional fields to "filter" out undesired task records.
I understand that the chart could have been done if the records were displayed in listview.
I don't know everything there is to know about charts, but I don't think that is the case. Form view, in fact, should work better so you don't see repeated copies of the same chart if your records don't fill the entire screen. Figuring out how to chart only the selected finance data from the related table will be the main challenge--especially as you have no direct link between contacts and finances. (the link goes through tasks and this requires an existing record that links to contacts and to finances before the data can be accessed from a Contacts layout.)