@Jay Hinrichs I’d love to hear your thoughts a little deeper on this topic-avg 7-10 yr hold of an investment property.I agree with comments to OP on taking 10 yr ARM-can refinance when rates are favorable.I’m 5 years in to REI and not really looking to sell anytime soon-is the cliff notes version that ROE becomes so lousy compared to a 1031 that the astute investor just sells and trades up?

You always could put $1 as co-op now you can put $0.

I have 120 units, plus various keys for common areas, coin-ops, etc.

I know for co-ops some board members will not allow you to even rent your co-op.

Not sure the OP has looked into the deep hole of legality on this.

IF     the OP and the Seller signed a tax reproration agreement, then he should follow the terms of that agreement or risk being sued as mentioned by our Moderator.In Illinois, the parties agree that Seller will give Buyer a tax credit based on the most recent tax bill prorated through the date of closing plus 5-10% to handle tax increases in the future. 

This would not include the OP’s labor.  

The OP of this thread obviously wants answers.

Speak to all 3 as adults, get their plan of attack, modify the lease accordingly, let them know the plan should they pay or should they not, and get moving accordingly.It sounds as if the OP is already dealing with the problem of not receiving full rent and delivering a pay or quit notice, so I think they will be on the path to re-renting soon.

@Henry LazerowI agree re: leverage. once the OP gets started he will realize the power of leverage and realize that the return seen on paying off a house is better spent acquiring the next deal with 25% down.