NEW YORK ( TheStreet) -- Today's buy-and-trade earnings previews focus on eight companies in six sectors that report quarterly results premarket Tuesday including Dow component Home Depot ( HD) and electronics and appliance retailer Best Buy ( BBY).These stocks include three from the retail-wholesale sector, and one each in construction, consumer staples, medical, oils-energy and transportation. The construction sector is 20.7% overvalued with an underweight rating. Of the 158 stocks 54.4% in this sector have sell or strong sell ratings. The consumer staples sector is 23.9% overvalued with an overweight rating. Of the 260 stocks 41.9% in this sector have buy or strong buy ratings. The medical sector is 25% overvalued with an equal-weight rating. Of the 774 stocks 60.5% in this sector have hold ratings. The oils-energy sector is 18.9% overvalued with an equal-weight rating. Of the 551 stocks 58.8% in this sector have hold ratings.