sorry, but you somewhat implied you could not afford the dog in your post.
"Also, if anyone knows of a place I can take her to get checked out for free or little cost". This somewhat gives readers the impression you cannot afford a dog.
In addition, you state you are not a dog person. "I am in NO way a dog person"
By stating this those who are knowledgeable regarding dogs will obviously question how you could know its condition. Dirty does not mean well taken care of.
Before you assume anyone is passing judgment it would probably have helped if you had just re-read your post and included all pertinent information. I have no doubt you care about the dog or you would not have posted in the first place but the post itself leaves readers to assume whether they want to or not since it does not clearly stipulate the steps you may have taken such as calling the police. That was not noted in your original post as would have most likely changed some of the opinions with regards to answers given here and led to less of what you are deeming derogatory remarks. No one is necessarily telling you what to do but pointing out what should be done anytime a stray is found. Do you have a local
craigslist classifieds: jobs, housing, personals, for sale, services, community, events, forums for your city or community. Many people when they lose dogs will place a notice on the lost and found and pet section on there as it is free for anyone to use and is viewed by a large number of people daily. Before you decide to keep the dog it might be best to find out if in fact someone has lost the dog and what you are seeing is a dog lost which therefore looks bad. Remember what you said, you are not a dog person so it is possible that maybe you are seeing something that really is not what you think. Many of us here work with dog rescue groups so yes we are constantly looking to find owners who have lost their dogs. If it was yours and was in fact lost, would you not want to see it returned. Just asking that you see the situation from all sides without making any assumptions.
THis dog wandered onto my porch today 
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