For my house sitting experience I’ve had to stay overnight at my uncles house and my cousins many times and watch their dogs while they are gone, I’ve been doing that for probably 5 years. I’ve also house sat for friends and other families and taken care of their dogs (and cats!) for quite awhile. For dog walking I’ve always had dogs, I’m good at walking them but I’d prefer (especially) for bigger dogs to be trained for walking so They are not just pulling against me the whole walk. For drop in, I’ve had to do them for years whether your dog is on a specific schedule like my dads or not I can play with them feed them and any other specific doggy request. Same for cats, I’ve always had cats as well and I’ve never met one who didn’t like me :) I’m not professionally trained as I have not taken any classes. but I know how to help both choking cats and dogs! Or know how to help if any other emergency might happen.