My post wasn't to imply that you are a bad person. So please, let's get that out of the way. I merely was replying with my opinion to your post, "What to do with stray kitty?" I was answering your question with what I would do, my opinion.I think you have a big heart and have fallen in love with this little fellow.
While there is a chance that the kitten was dumped, there is also a chance that it was "not". I don't believe that checking with a few neighbors in your mobile home park is enough. No one is perfect, equipment is not perfect and if that kitty by chance escaped from a collar or a carrier by someone passing through town, someone who doesn't know the area well, staying with friends, families moving, someone taking their kitty to the vet, etc., your mobile home park is not a wide enough search area for you to cover and it is possible the owner does "not even know to look there." The owners could be frantically searching for this little guy all around you. They could have lost their pet miles from where you live. This also doesn't make them irresponsible. It could just be bad luck that this animal escaped from things I mentioned above. That is why I would be reporting it to the local animal shelter, the police, local vet offices and such. These are the first places I would be calling if I lost my beloved pet hoping someone reported that they found them. After all, if you lost Thomas again, and you couldn't find him in the mobile home park, wouldn't you be calling these places in case he wandered further away from home than you would have expected?
My suggestion is what I would hope someone would do for me if God forbid my pet slipped out of my grip, or my child's grip and ran. Also, during the Fourth of July festivities more pets run during this time of the year than any other. The booming of fireworks can cause animals to run for miles. They can be terribly frightened. This is a possibility considering the 4th was only a little over a week ago.
This cat has been handled by people before you. It is not a feral cat or you wouldn't be able to get it to lay on your lap. It wouldn't be as friendly as it is. If someone dumped him. Shame on them. If they lost him, my heart goes out to them.
In answer to your question, all I am saying is this is what I would do. I, personally, could not sleep a wink if I thought I didn't do everything to make sure that a lost animal was reunited with it's "rightful family" no matter how much I liked that animal. If no one claims the animal in a reasonable amount of time then I could sleep well knowing I did my part. Then if I chose to keep the animal, I could enjoy it fully without a heavy conscience. I couldn't call it "mine" until I did that. It would only take a few phone calls to be sure.
I guess I am a big believer in "Do unto others what you would want done unto you." It speaks volumes.
Best wishes.