At this point whichever is the deed holder is the only LLC that’s truthfully needed.

(A) Any security deposit in excess of fifty dollars or one month's periodic rent, whichever is greater, shall bear interest on the excess at the rate of five per cent per annum if the tenant remains in possession of the premises for six months or more, and shall be computed and paid annually by the landlord to the tenant."

Do the math with a small number of units you like best and purchase whichever one makes sense financially based on price/income.

I want to buy the property on terms and demo, build a new house.I want to structure an owner finance deal with him where I either pay him interest only on the lot or no payments for 18 months (or until the new house completes and sells whichever is earlier). 

Preferably whichever one is cheaper to fix and/or will bring the better return. 

The maximum occupancy permitted in a vacation rental unit is two (2) persons per bedroom larger than 100 square feet, plus one (1) person per bedroom greater than 70 square feet but less than 100 square feet, plus two (2) additional persons, or a total of eight (8) occupants, whichever is less.The homeowner must post the required information on the property.

Which events are the best to attend? 

I always say to go follow different people that offer STR masterminds/courses on social media, and whichever one clicks for you and has similar goals consider joining the group.

Hey @Tom Brown - I'd echo @Paul De Luca and recommend @Samuel Pavlovcik, but also through out @Prashanth Mahakali...both are awesome Chicago architects and good friends.Things have changed with the City of Chicago, but probably not enough...whichever architect you work with just make sure that they are self certified which can drastically speed up the process.What neighborhood is your property in?

Note that you typically have two years from the date you paid the tax or three years from the date you filed the original return (whichever is later) to submit an amended return.FORM 3115This is a specialized IRS form that is used to request permission to change an accounting method.