It's often cheaper and you'll have better results using boiled chicken breast as a treat rather than treats you buy at the store. Buy a huge container of chicken breast at the store. Boil it up and bag it up in the fridge. Freeze what you can't use this week. Cut it into bits and get a treat bag to wear at your hip.
When we are at home we mostly use my dogs own kibble as treats, because he works for almost all of his food. What I mean by that is that he never eats from a bowl. We use meal time as a way for him to get mental stimulation- he either gets his kibble by doing training exercises or he eats his kibble out of a Kong. This helps them be more food motivated as well as getting them used to the idea that they need to "work" for food, or in other words, do the behaviors that we want in order to get food. If your dog gets overly excited by treats and cannot focus using their kibble can also help with that.
When I am first teaching a command I use something very high value. As they get better at it I phase out the high value treats. I have kibble and chicken mixed in my treat bag at all times at my hip. Since he listens well in the house we use kibble unless he is learning something new. On walks or anywhere there is an increased level of distraction I use chicken. It sounds like there might be a lot of distractions in your house with so many people. So try to set aside some time when you are alone with them to teach the behaviors. Then graduate to rehearsing them with more distractions later.
My puppy was a serial leash biter when I got him at 3 months old. He is now 4 months old and this behavior is almost entirely eliminated. First step was teaching him the "drop" command. Second step was implementing an "earn it" program with him. The concept of "earn it" is to reward the dog for calm behavior. The ebook is available on Amazon for .99 and I highly recommend it. It is very simple. You reward the dog when it is calm.
An example for going on a walk would be: if the dog flips out the second you grab the leash off the hook, put it back. Repeat until the dog is calm when you grab the leash. Before you put the leash on, the dog should sit. Don't give a command, just be patient and wait for them to sit calmly. Hook the leash on. If they start biting it either 1. Do nothing, wait for them to stop (this is what I am doing now as he is getting better at "earn it" or 2. use drop it, say yes and reward. Now for leaving the house, the dog should still be sitting. If they aren't start over with waiting for them to sit. They should sit calmly while you touch the doorknob and open the door. If they don't repeat until they do. They should sit calmly until you give them a "go" once the door is fully opened. They should leave calmly with you and not fly out the door. If they do, start the door opening procedure again. It makes leaving the house take an extra 5 minutes but once we start the walk the dog is calm right off the bat.
Before your dog leaves their crate/play area they should also be calm in a similar manner. Wait until they sit calm. If they get up the second you reach for the crate latch, pull your hand back and wait again. Never reward impatient behavior. In this case, the reward is coming out of the crate. It might take 10 minutes to get them to clam down, but by rehearsing this behavior and ritual you will teach the dog that they get what they want: the freedom, the walk, the food, the toy, etc, by being calm. Hope this helps ! https://www.amazon.com/gp/product/B007WU6MTY?ref=dbs_p2d_P_W_kindle_available_T2