taxpayer has added expenses

thermospatub $18,060

chemicals $260

sundex fiberglass $7,424

new heating and ac $12,000

masonry $6,573

water pump $3,790

He has has shop/home office. Do these need to be depreciated? How do you know if it an M home office or N home office improvement? Or does this just get added to repairs and Maintenace or other expenses?