However, we typically do replace the windows on our BRRRR if they are old, typically single pane, typically aluminum. 

For flips - here are some criteria borrowed from the dummies book for flipping: Steady or rising real estate values, Multiple offers on recently sold homes and homes currently for sale, An influx of homeowners moving in from other areas, A decrease in the number of homes for rent, An increase in the number of homeowners in the neighborhood moving into bigger homes rather than moving out, Older homes — homes built at least 20 years ago — and homes that generally require more rehab, Areas with aging homeowners — homeowners who may be downsizing or retiring, Visible updating in older neighborhoods — new roofs, aluminum replaced with vinyl siding, replacement windows, modern earth tone trim paint, City improvements including street repaving, new street lights and street signs, and repaved sidewalks.

Aside from the usual mechanical evaluation for any property in older homes you need to pay particular attention to lead, asbestos, and electrical (aluminum/knob and tube). 

I am a 24 year old living in Southeastern Wisconsin.

I'm finishing a flip but the latch of this aluminum window is broken..

South Eastern WI is a great place to have on your radar including but not limited to MilwaukeeWhat are you looking to spend?

How are the gutters and downspouts (original wood or aluminum)?

Feel free to DM me anytime and I would be happy to share our experiences here in Milwaukee and Southeastern WI.

It certainly wouldn’t make sense if one has a “finished” building, but in my case, this building will be near down-to-the-studs anyway, so installing the PEX/aluminum fin system would be achievable.  

I carry an aluminum bat in my car.