The cost of a fabric, or how heavy or substantial it feels, does not indicate whether it will be suitable for upholstery. As a guide, some manufacturers use the symbol of an armchair to suggest that a fabric is suitable for upholstery, whereas others use a new A, B, C system to grade the durability of fabric.
Those rated "A" have a rub test number between 21,000 and 40,000 and are considered suitable for "severe domestic" use; a fabric in this category would suit a sofa, for example.
Fabrics in category "B" (rub test 11,000 to 20,000) are suitable for "general domestic" use, for example, for curtains.
Category "C" (rub test 4,000 to 10,000) suggests that fabrics are suitable for "light domestic" use - this covers items such as cushions.
These ratings may be shown on pattern books but, if they're not, you'll need to check their suitability for your project with the manufacturer.
Also, be aware that upholstery labels must give the fibre content of the fabric, and should indicate that the item has met fire safety standards BS 5852.