Suponsor eligibility for I-864

[orgcudede]

After having my university education in a foreign country I came back to US on Feb 2011 together with my parents. I'm an USC and my parents are in US as tourists. I will file for them I130 together with I485 as they are my immediate relatives. I rented my house, bought my car and as of April, I have a part time job which I make around $15.000 and I saved money while education and have $20.000 in my savings account. I think these two will work to reach the $23.163 poverty level. I never filed any thing about tax and I don't have a tax background. So my question is: Will this be a problem when I will be filing the I864. Am I eligible enogh to sponsor my parents an when will I fill the I864. Thanks for the answers.