I've noticed that the more stays I have with the same dog, the less they listen to me. It's like the first time they're on their best behavior and then after that they don't seem to care anymore. Have any of you experienced this and is there any way to solve this problem?
I have a few times. I feel like, once they become more comfortable at my house they tune me out :) Treats usually work the best for me, especially when they decide they don't want to come inside!
I experience the opposite - the longer I have a dog with me, or the more often I care for them, the better our communication gets. I don't use a lot of learned commands with my guest dogs, because I don't have that relationship with them, they may be too anxious to respond, and I just don't find it necessary. Instead, I tend to talk to them, using my own cues for letting the dogs know what I'm doing and what I expect, like "let's go" when we start moving on a walk, "come on" if I need them to change directions/catch up, "yes!" for doing something I like, "nope, try again" when they do something I don't... After they've been with me a while and on return visits they are pretty familiar with what I want, and I can use my cues with them pretty effectively. One of my guests I've taught to stop barking at people outside my windows by using "make good choices!"
I talk with my guest dogs too. I'm still trying to get "make good/better choice" catch phrase that I'm borrowing to work - that's really great.
It's a useful tool - mostly because it reminds me that it's far more important for my dogs to make good choices given a million different things they could be doing than to have them "well trained" to do a handful of things on cue when I want them. I could always ask them to sit and wait for food or treats, or I could encourage them to make those choices on their own, without being told every time.
I agree with Amber. Sounds like the dog is getting comfortable and showing his truer colors. ;) You may have also subconsciously changed something, too. What, specifically, are you having problems with?
Sorry, I've experienced the reverse. The dogs I care for repeatedly look at me like second mom and my dog as their role model/buddy. I'm not sure how you'd solve it.
Perhaps reinforce training commands with small practice sessions before meals and walks (and maybe on walks if you can). It's helpful to work on the vocabulary their parents taught them. To strengthen the bond, other than lots of quality play and walking time, you may consider hand fed meals to re-establish yourself as a resource giver.