Equipment question?

So I have been brewing for a few years now and my wife is interested in making wine. Not sure if this will be for her as beermaking is for me (hopeless addiction!) so I really don't want to buy special winemaking equipment. How would it work to use my fermenting bucket and a 5g carboy secondary? What other equipment would I need?

You don't NEED anything more than that other than some additives (ie. yeast nutrient, energizer, pectic enzyme, tannins, etc...). These are often listed in recipes so you can buy them as the recipe calls for and depending on how you want to experiment.
Some people say that it is not a good idea to ferment any wine in plastic but I had no problem in the few batches I did as long as you only use it as a primary as you stated.

well, you should be good but all the kit wines I've bought (which admittedly is only two) have been for six gallon batches so you need a seven gallon bucket for fermenting and a couple of six gallon carboys for aging. You also need to degas wine and they make a drill bit attachment thing you buy cheaply to achieve that. Other than that I think your good, it's super easy. Unless you want to do fresh fruits, then I think you need a press.

Rather than buy a 6 gal carboy, you can use your 5 gal carboy plus a one gal jug. If your bucket is 6.5 gal, i'd start it with a little less water, then top up when you go into the carboys.

For degassing, I just rack back into my bucket and stir with a spoon.