I know this might seem strange on the face on it but, if I get an additional apple developer account can it be used on the same Mac or will there be problems? If so, what might I need to do in XCode to switch between accounts for different projects/solutions? Thanks.
You shouldn't run into too many problems if you have additional Apple developer accounts. I do this all the time for my various clients & customers who I have to separately submit & maintain apps for.
Just make sure you set the right provisioning profile for the app you're trying to build in that app's project settings and you'll be okay.
The only thing I can think of where you might have a bit of trouble with might be submitting the app, as Application Loader is a bit stupid in how it (doesn't) handle switching from one Apple ID to another (and here is a related question with an answer that solves that problem), but in general if you're handy with Google + StackOverflow, you'll easily find ways to jump over these hurdles.