What gear do I need for multi-tracking vocals

I need some advice about gear and multi-tracking vocal recordings. I want to do some acapella vocal multi-tracking. I’ve seen a lot of it lately on YouTube, with one person recording a barbershop tag, and usually including a video with screen split four ways. But there’s little information on exactly how this is done. Is there anyone on this board who has experience in this?

I think I will need to have the following gear to do this:
-A microphone (have an AKG C3000) condenser mic
-pair of earphones (I’ll get something like a pair of Sennsheiser HD 280 Pro
-recording software (I have an old Cubase, but will probably use either Audacity, Reaper),
-a computer (I have that);
-an appropriate soundcard either in a PCI slot OR a standalone audio interface (I’m considering buying the EMU 0404 USB).

Is there anything else I would need?

I have a Yamaha MX 12/4 mixer, but I’m not sure how that would be a useful part of the gear. Or am I wrong?
Also, I’m thinking about getting the Fostex MR 16HD digital recorder so I can be more mobile and also use it as a scratchpad for my harmony recordings and only need to take the microphone and a pair of earphones. Am I correct in assuming that? Can I get presentable results using only these 3 pieces of gear?
I also plan to do some songwriting and arranging with this setup.
Again, is there anyone in this forum with experience in creating a ‘virtual’ acapella group through multi-tracking?

Any comments on the above would be appreciated.

<<<-a computer (I have that); >>>

One of the problems with these forums at the bottom is people never tell us what kind of computer they have, the operating system, or version of Audacity.

It makes a big difference.


My mistake…
It’ a PC, P111 at present. A upgrading shortly to a dual core with lots of RAM.