The Contello was probably made in the 1980s ... possibly a little earlier or later, but not much. The Scandalli is from the WWII era.
The Contello is a 3-reed, non-pro model, with a rather obscure brand name. If in very good playing condition, something like this typically sells for around $200-400, unless being sold by a dealer who offers a warranty, which can add a little more to the value. If it needs any repairs, the cost of those repairs subtracts from the value. Accordion repairs can be labor-intensive and therefore, they can be costly in some cases.
Scandalli is one of the top brand names. However, this is not one of their top-of-the line models, so it probably does not have professional (a mano) reeds. The labels on the shifts make it difficult to tell whether it's a 3-reed or 4-reed accordion. We'd have to see a photo of the inside to resolve this. Being so old, this accordion will need a complete reed skin/wax/tuning overhaul, new valve pads, new bellows gaskets, and possibly more, unless it has had these things done within the past couple of decades. If it has had all of this maintenance not long ago, it should be in good playing condition, worth up to $500 if 3-reed or $750 if 4-reed. However, a complete reed skin/wax/tuning overhaul costs about that much, so if it needs that, the value is very little as is.