If your lawyer does not know (according to you), how could we possibly know the value of the house, what the Trustee will do, or anything else about your case? As far as how long you wait, it is until the case is closed or the Trustee states he has no interest in the property. It may be different there, but in Georgia, tax value is rarely fair market value and will not be accepted as such. Talk to your lawyer.
Your discharge will come about as a matter of course 60 or so days after the meeting of creditors. On a parallel course, the trustee is deciding whether you have any assets that can be liquidated and paid to your creditors. If your equity has been properly exempted, the trustee will not be seeking to liquidate the property, and will file a no asset report. Your tax commission assessment is likely higher than reality, since this is the basis of collecting taxes, which the government relies on.
First, the law required and you signed under penalty of perjury of what your property was worth. If you put down the property tax value instead of the value of what it was really worth then in my book you lied..perjury. You do NOT want to hear that ..but it is the truth..the law you signed said the value. Now, having said that. it is easy, you can wait to see if the trustee sells or tries to sell your house or not..as if he does not, and the case is CLOSED (not discharged but closed) then the property is deemed abandoned and you can do with it as you want and don't have to worry about the trustee trying to sell the property. The trustee can keep open for many many months if he wants...but once closed, it is over! So, once you get your discharge, call the court 10 days or 12 days later and ask (1) did the trustee file a no asset report, and (2) if he did is the case closed. Good luck and I hope my answer assists you in your case.
If all the trustee did was ask questions about how you calculated the value of your house and you replied that you used the property tax bill and you have not heard from the trustee since, there is no problem with your case. You will receive your discharge in about a week, if you have done everything else. In Utah the trustees will accept the property tax valuation as accurate enough for most purposes.
This is not legal advice and I am not your attorney until you retain my office. Always consult with an attorney in your area before acting on anything you read on the internet.