Have some lenience for her dogs They have essentially been uprooted from all that they've known and are living on foreign territory with an entirely new schedule (if there is one at all!). These little issues are all a very normal for drastic changes in a dog's life.

1. The "miniature" greyhound (I assume you mean either an Italian Greyhound or Whippet?) is not understanding your dog's desire for personal space, so continue what you're doing. When the greyhound gets in your dog's space, just body block him and give him something else to do somewhere else. Or you can recall the greyhound and redirect. Verbal reprimand "AH!" and redirect. Basically, punish and always redirect.
2. Do her dogs have a potty schedule at all? If they do and they ONLY pee when you're not there, then I would suspect that their behaviors are anxiety related. Many dogs develop these problems when they undergo drastic changes in their lives, such as moving to a different home or family. If they don't have a potty schedule, somebody has to teach it to them from scratch again (tough work, but it'll hit the core of her dogs' problems). Also, if her "miniature greyhound" is really an Italian Greyhound, be aware that Iggies are NOTORIOUS for being difficult to housebreak. I don't know what it is! They're just ridiculously hard to housebreak. Most Iggy owners concede by having a litterbox in the house.
3. Does the greyhound get a lot of exercise? If not, his barking can be a product of boredom. But if he does get a lot of exercise and he's still barking, then you need to punish and redirect. Punish the barking by shaking pennies in a can, verbal "NO!!", etc/whatever. Then, redirect by turning his focus back onto you or playing with the other dogs.
4. Like I said, do they even have a potty schedule? It seems to me that there is a major disconnect between you and your friend's training beliefs. The two of you aren't on the same page, and it seems like her dogs are suffering if they have to pee on their bedding. I would advise you to tell her to draw up a potty schedule ASAP. She should try her best to fulfill it. But if there are days that she comes home too late, let her know that you are willing to let the dogs out maybe once or twice a day. Work together, and the pups will benefit

Meanwhile, be calm and keep going about your schedule the way you were before. Your dogs (and your friend's dogs) will greatly appreciate the stability!