Plumbing ground is put in and inspected / Cables and material for the slab are delivered around the same time5.

The house is solid structurally and in a great area that I expect to appreciate, but I need to replace plumbing, electrical, add a bathroom, and paint the entire house inside and outside. 

This may not be what you want to hear, but you are way better off buying a property that has had systems (HVAC, electric, plumbing) updated already.

Before you swing a hammer, confirm clean title, redeemed taxes, code liens, and permit history; get utilities on and do a full safety check: roof, foundation, electrical, plumbing, HVAC, and sewer.

For the Pilsen property, what's the age of the roof, mechanicals, plumbing, electrical, windows, etc? 

Life-safety and habitability issues (like plumbing leaks, HVAC, or electrical hazards) are usually handled immediately, but make sure your management agreement defines those clearly.

For an 8–12 unit in your area, pick a tight buy box and underwrite like a business: verify in‑place rent rolls, trailing expenses, and any deferred CapEx (roofs, plumbing, parking).

If you use subcontractors that cover multiple trades, like roofers can do gutters also, or HVAC guys sometimes also do plumbing, then they a lot of times agree to reduce costs in order to get awarded the work for both trades. 

Material prices have continued to rise, particularly mechanical/plumbing supplies, but it's been gradual and no changes within reasonable rehab life cycles that are truly profitability altering.

Your feedback is really shaping what I build next.Quick question - when you track renovation costs, do you prefer breaking it down by room (kitchen, bathroom, etc.) or by trade (plumbing, electrical, etc.)?