I can't get my dog to stop peeing in the house. Tried many things. Please help!!!!?

A little over a month ago I adopted a Shiba inu mix from a family who didnt have enough time. He is 7 months old and was potty trained when I got him. I knew there would be a period of adjustment but it's been almost a month and today he has peed 4 times. He has is good days and his bad. He goes outside and sometimes within a half hour he pees. It's almost like he doesn't really care that he's doing something wrong. He's not sneaky about it at all. He'll pee right infront of me. I take him out every few hours and take him for walks but he still pees inside as well. Ive tried telling him bad dog and taking him outside to pee. I've rubbed his nose in it and swatted him. Hes crate trained but I refuse to keep him locked up all the time. I don't know what else to do, I will have to return him to the family if I can't get the peeing under control. I don't want that but can't have his peeing everywhere. Btw he's not marking either. Please help!!!