The second you go off-site, you are creating way more liability for yourself.

Any liability I can avoid by having them install their own units?  

You need to get rid of your biggest Liability first!!

If you do decide to have a "partial" 1031 exchange and use some of your 1031 sale proceeds to pay off debt on other assets, you'll just want to make sure that the improvement in cash flow offsets the tax liability that you incur from your partial exchange AND the lower rents from potentially buying a less valuable property with your partial 1031 exchange. 

Does the realtor/broker hold any liability for not addressing it in the contract?

@Jonathan Snider another con may include the fact that you will now have multi state nexus and tax liabilities, which often times increases complexity for unaware investors

The attorneys are very good at liability. 

But transferring liabilities could be.

From deductions for mortgage interest to depreciation benefits, there are numerous ways to minimize your tax liability and maximize your returns.

This can result in higher depreciation deductions in the earlier years of ownership, providing tax savings.Tax Situation: Consider your tax bracket and the impact of increased depreciation deductions on your tax liability.