No attic/ventilation.. is this a problem?

[Jared Garza]

I’ve found a property which is 3000sqft 1 story home. The back portion of the home  was added on and that portion has no attic. It’s about 3/4 of the total house. The front portion has an attic and ventilation but the back part does not. The slope of the back portion is about 12/4

In the hot Mississippi summers I'm not sure how badly this will affect the temperature and also if it will affect the ARV of the property or not. Without considering the roof situation the property needs about 70k repairs to get it into great condition. ARV 140-170k, purchase price 35k.

If anyone could give me some pointers I’d greatly appreciate it!