Hey hows it going, obviously not good. What exactly is the temperature in the enclosure? I just noticed you haven't bought heating for him yet and you have had him since around September 18th, that's when you did your first post. Even though they burrow to get out of the heat and direct sunlight the ground is still somewhat warmed up from the sun, or in this case the heating source being used. Even though the air may seem fine without any extra heating that substrate may be to cold and he isn't digesting fast enough making his appetite slow down. The other thing im thinking is if you got him from craigslist im wondering if the previous owner was having the same problems and that's why he was getting rid of it. Another thing is do you know were the previous owner bought the frog, if he was running into problems right away and didn't have any test done you never know your frog may have some kind of parasite or worms which would really cause him to act off and stop eating. I know you said earlier in the post that your low on funds but a vet visit may be a good idea or even if you know of a good reptile amphibian store near by you may be able to call them and they give him a look over and may be able to notice something else that your missing. Just because that guy said he was eating for him you never know he may have been barely eating at all. Either then that I cant really think of anything else at the moment if everything else husbandry wise is ok.