No problem DavidBailey :) I'm glad to have cleared things up for you. If possible, since it is less than a gallon, I would go for 100% once a day... maaaaybe 100% every other day, but that's only if it's like .8 or .9 gallons. Anything less than that you'd need 100% daily.
I remember when I first got into betta keeping (just a bit over a year ago actually O_o), I kept my first betta in a .5 gallon for maybe 6 months. For a bit I did a water change once a week. Yeah, he seemed alright. Then I joined the fourm and learned better. I took an extra 5 minutes out of my life to change his tank 100% once daily, and he honestly started looking even better than "okay". Then I got him a larger cycled and heated tank and kept up with water changes, and honestly I had never seen him happier. It doesn't take a lot to properly provide for a betta. A tank large enough (IMO 2 gallons) to explore, clean warm water, good food, and wha-la... you have yourself a super happy betta! The prices of the most vital things like heaters may be rather high, but just remember.... bettas can live 5-7 years, so the investment in the long run will seem like little to nothing. :)
Just so you know, if you are low on money, there are typically some great deals on craigslist for tanks, heaters, etc. I check there every now and then, and I've seen some great deals.
And JKfish is not JK-ing. :D
that made my day XD