If you are not helping to qualify, you typically wouldn't be on title, so you'd have a separate legal joint venture agreement showing your interest in the property and the splits. 

Or would I then have to file a separate US return for the business?

As soon as that renovated property was rented I purchased a 3rd duplex witch didn’t have separate utilities.

Etc, etc, etcYou should at least find out who he is and run a back ground check.In addition, you would have to evict him separately from you tenant if it ever came to that.

Keep your books straight from day 1 - saving receipts, opening up new accounts per property, getting a business cc to keep costs separate.

The LLC, being a legal entity, has to be operated separate from yourself and not as your alter-ego. 

I'm sure nothing new for local appraisers, would be interested how they end up pulling comps/valuing it (ex. will they value it as two separate houses, one big house, etc) Best of luck with the appraisal and the refi!!

Some DSTs contain many (I've seen up to 20 separate properties) properties in a single Trust.Due diligence should include, ground-up property information (current occupancy rate, current rent, etc...), geographic considerations (population in the 3 and 5 mile, population growth, rent, occupancy, and cap rate comps, crime statistics, traffic count), sponsor/general partner track record and expertise, asset class considerations (it is possible to invest in an asset class with a small amount of equity that you may have no experience in), master lease, exit strategy (you do not get to control the exit, the general sponsor will trigger the exit based on their goals and objectives).The other thing to consider is that sponsors will sell equity on a first come first serve basis.

@John JeffreyCongrats on getting under contract.A tip for new investors is to open up a separate bank account for your business/rental related activities.

Each duplex is individually metered gas and electric, the water/sewer/gas is shared and the previous landlord has been paying that separately.