I would talk to them more, find out what the issue really is.

It's fairly typical an issue real estate types face when they start out, I was in the same situation years ago when I first got started.

There is also a provision detailing what cannot be used as a window covering: foil, cardboard, towels, shower curtains, throws, sheets, etc.  

I do 24 places on a big sheet of cardboard with 24 horizontal rows and 5 sets of 7 vertical rows. 

I thought we were removing the moldy wallpaper over paneling, but in many areas it was wall paper over cardboard walls. 

If you want to do it temporarily and without opening up the trunk line, then close the vents and tape cardboard on the inside of the vents.

If you go beyond their FICO score and give that person a chance, they understand quite well that if they blow it, they're going to be living in a cardboard box.

The zoning issue relies on understanding the local rules, whether the subject property was grandfathered in (zoning rules changed after the house was already occupied as a duplex with the proper permits, etc) or the property owner made it a duplex without acknowledging the fact.I helped buy nine properties while out of state.

Of course, lots of people go to IKEA in Atlanta and that seems to be the new craze in boxed cabinets , but I really can't stand IKEA cabinets with the  cardboard back and the cheap metal bracing.

It was an REO but since it's a college town, I've never had an issue renting it once I fixed it up.