Connecting multiple ADC''s and DAC''s

Archiver

I have a project which is seriously challenging my I/O pin count.
What is the expense, in pin count, of adding an additional serial
input device? It seems to me that it would be possibly to use one
synchronous serial ADC and four sychronous serial DAC's using only
six pins - one pin shared by all for clock, one pin for each device,
thus costing only one additional pin per device added. Is this valid?

Thanks

Bob Pence