You haven't done this yet? Please hire yourself professional accountant.
For the most part, a partnership must file a form 1065 tax return, which issues a K-1 statement to each partner reporting that partner's share of income and expenses. The 1065 is due March 15 instead of April 15, and the minimum late penalty is $195 per month per partner. The K-1 is added to your regular tax return along with other income and expenses.
I believe the partnership can divide the partnership income and expenses in any way that the partnership agrees, although that may depend on state law. The income from the sale would be reported on the K-1 that you attach to your tax return, so if you agree to take all the responsibility for this transaction, that might be allowable. However, it can get quite complicated, especially if you also have ongoing expenses and income (is this a rental, or a flip? Or something else.)
This can be complicated and the consequences for screwing up can be severe, so you really would be strongly advised to get some professional help.
