If not should we open a joint card?

We just had the same leak occur at the poured wall/cement flooring joint (built 1978).

If you file a joint tax return then it is that tax return that is the taxpayer for the old property and it needs to be be the tax payer for the new property. 

The costs associated with setting up the PPM (Private Placement Memo) and getting it legally ready to take to investors would kill most deals of that size.If the smaller commercial multifamilies in that range (6-12) still interests you, you are more than likely looking at a joint venture.

This is a follow up to the thread I posted here: https://www.biggerpockets.com/forums/311/topics/59...It appears that multiple buyers can get a joint residential mortgage together, so that is solved.My question now is around condo conversions.

Depending on your tax filing status, Single, Married Filing Jointly, Married Filing Separately - you may be disqualified from taking this very valuable tax deduction based on your income and the nature of your business.

Joint venture > Silent money parter would be my two choices.  

If you have a self-directed IRA you could utilize those funds or you can joint venture with an experienced note investor. 

Also there's another tenant who we'd be happy to keep and is jointly liable.

I personally think it's probably difficult to see dramatic changes in your financial portfolio due to TK investments unless you get lucky with appreciation.Finally: If you are looking for an extremely passive investment, you can consider crowdfunded REIs and joint ventures.