Think I'm ready to start kegging?

I got the 15gal keg basically for free, I got the 2x 5gal corny kegs with sanke adapters on the left for free, and I got the 5x 5gal ball lock cornies for $20 each... and should be picking up 2 more ball locks this weekend. I got several disconnects for the ball locks included. Just need to buy some more, and maybe replace a few of the gaskets (gonna pressure test once I get a regulator).

Picked up the homemade IC for $25 as well.

I got the 20lb (empty) CO2 tank for $50, and traded it for a full one for about $17.

All I need now is a regulator, some gas and liquid tubing, and something cold to store them in once they're full of beer!

Question: as far as tubing goes, do I *have* to use the red CO2 tubing and clear tubing that you get from the online/local beer places, or can I use vinyl tubing bought at home improvement stores?

Beverage line is smoother on the inside than regular tubing. Doesn't matter for CO2.

I just ask because its easier to get it local, was just wondering if it made a big difference in the quality of beer or longevity of the system?

Also, eventually I'd like to build a large kegerator or a keezer to hold at least 4 kegs at once on tap. Does it make sense to go ahead and get a dual-line pressure gauge so that I can keep the tapped beers under pressure with one gauge (and a manifold), and force-carb new kegs with the other? Or is it not a big deal to swap it back and forth?

I'd definitely plan on getting beverage tubing for the beer lines. In addition to the smoothness, I've heard horror stories of beer sitting in the lines developing a nasty plastic flavor. Haven't tried it so I can't say for sure, but I'd play it safe with the beer line. Gas line doesn't matter as much, I've used both the red and the clear and haven't had problems with either. I happen to have red lines now, but can't say why I went that way over clear, just figured it would be easier to tell the lines apart when they're jumbled together in the fridge.

As far as the regulator, if you normally force carb using the burst method (high co2 for short time), then a dual body regulator might be handy. If you only had a single, you'd have to either unhook or turn off gas flow for the kegs that weren't being burst carbed while it was turned up, but that shouldn't be a huge problem. The other option is to use the set-and-forget method, where you just leave it on serving pressure until it carbs (generally about 2-3 weeks). That way you don't have to worry about changing the pressures up, but it does take a little longer. If you get a good pipeline going you could even carb naturally in the keg and skip force carbing all together.

I've never used a keg before, so I don't have a set method yet. I will probably try force kegging and natural carbing in the keg, to see which works better for me. I'll probably force carb the first one just because I'll be too impatient to wait to try it!