stick to basics
you need pro tools
monitors
a good mic
and some sort of sound treatment

cheapest you can get pro tools is a mbox mini.... its like 250
monitors you dont want to get too cheap on... your lookin at least 100 to 150 per monitor
mic is key if you can match it with your voice....best over all mic within your budget is the st55.... trust
and than sound treatment... you can build a booth, treat your room but the most affordable, most travel friendly, and prolly the best sounding unless you drop serious cash is the reflexion filter.....

if your happy with the mic you have, you can cross that off the list, and what not but you need those four things for a decent set up

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