[Blue gumdrops]

So I've had Richie since he was 6 weeks old, I know I should've known better but I didn't at that point and his old owner didn't really care about him so I took him in. He's now 14 weeks old and he's driving me crazy. I've trained him how to sit so that was pretty good. I've tried and tried to train him to stop biting but it's only have gotten worse. He tries to bite my hands, arm, shoes, feet, and pants, literally everything. I know he's a puppy and this is what I have to deal with but I just want it controlled. This summer we're going to visit my family. And I have cousins who are less then 10 and a nephew who is 3. I plan to get my dog to not bite at all during summer but it seems impossible as I've tried and nothing works. My dog loves strangers. He doesn't bite them in fact he gets so excited and goes crazy for them. But I'm scared that once he's comfortable he'll bite. So what can I do at this point? I don't know how much classes are and I'm guessing they're over $100 which my parents think is pointless as I could do it myself. He also barks at my shoes when I try to pull them away and thinks I'm playing. I leave him for 10 seconds and Coke back to him and he does the same thing. I repeat the same process and he proceeds. I just don't know what to do. I'm desperate and stressed.