Replacement of roof in 2008 and windows in the year 2000. 

Also window units are very common in that area as well.

Here is a list of the work that needs to be done:Total sqft: 15751st floor: 9302nd floor: 645Lot dimension is 100'x150'Side driveway with access on the frontBack detached garage 1 stall access from alley wayInterior Floor 1First two rooms total of 408ft^2Carpets removedHardwood finishedWalls/Ceiling Painted w/ 8ft ceilingsReplace Windows - 3(2.5'x5'), 1(4.75'x5')Small Foyer 39ft^2Flooring (tile?)

Read your lien laws, maybe it shortens the window to file a lien.  

Its ok to have a 10k window, such as, the house having an ARV of 260to 270ish, but you do not want to have a 50k window.

We have been in a window of about 2 years where flipping is a solid opportunity in some markets, but that might stall out in another 12-24 months depending on what the economy does.I know the above is not an "answer", but perhaps a means to ask the questions that will lead you towards what is best in your situation.

So I walked onto the property and looked through windows and decided it was worth making an offer in it.

I also had budgeted new windows for the entire house. 

I'm in each of my units once a month at minimum and they know when they sign a lease with me that I know what tenant-caused damage looks like, and they'll be responsible for the repair bill when they break something ... window, door, toilet, faucet, switch plate, whatever.

There are construction projects unfinished, derelict houses with bars on the windows.