You can buy upgraded level before tax time and then reset.   

Even the doors needed replaced you can tell it was broken into multiple times...

Unless the job is only going to last a month, that payment schedule isn't broken up enough for my liking.

Upgraded units in the same complex are getting between $1300 and $1500/month at the high end.

This is one of those times that your simple upgrades can make for a great ROI 

Make sure you have an experienced inspector who also will give you an indication of life span for major systems.I'd create a sophisticated spreadsheet with as many costs broken out as possible. 

At least one window is broken out. 

I have kind of assumed the city is broken in the four corners. 

They won't realize that $350K without putting in at least an additional $100K in upgrades, in addition to the $30K I would have put into it.

If the property has any issues that would cause someone to not be able to live there (roof, plumbing, broken windows, holes in the walls, etc.) those items would come back subject to repair on an appraisal and need to be fixed before you can get any type of mortgage financing.