and congrats on choosing Chicago as your first home hacking destination!

(If you are doing a HML you will have to pay some loan points and depending on the terms if you are using a PML you also might have loan points)What about the closing costs when buying the property it seems you left those out, but correct me if I am wrong but for the price of the home you are buying and selling 20k for both the purchase and sale of the home seems a bit lowAs for your rehab budget, I would say you are almost on the money I would say 85k is a good budget to go by which is about $40 per sqft plus extra for that roof and possibly some pest controlAs for your realtor giving you the ARV of 600k, I would ask how she/he got that number and ask for her/him to send you the comps she/he got so you can make sure they are suitable comps.

I would think it depends on your strategy.  

I still do that as well as some average starter home flips Though not recently due to market conditions last few years.I have crews that are 1099 and others on payroll so I have a mixture depending on the trades and the projects I have on my books.

Bart, it just depends on what your investing strategy and your priorities are.

There will be no power for a day or two depending on your licensed contractor.Plank or batten box house is same as a log house (can't conceal electric or plumbing well), I would make them safer.  

I think it depends on the property and numbers.

(Depending on what they're selling, probably not six figure nice, but newer and well cared for). 

I think it depends on your rental strategy.

The home seller isn't telling us anything) Depending on the demand of the area as well , also to repair the issue that mentioned above is not that problematic , if neighborhood value is 2 mil you sell 1.7 I would buy in above condition