Help my dog and fleas now getting bald spot Vegetable oil and more baths?

Long story. But I just moved into a new apt. Just my luck 1 neighbor lived like Sandford and son, really bad conditions (like hoarders) just moved they had 2 dogs. My dog nevered had fleas, Another neighbor 2 doors down found 2 fleas on his dog. So I give my dog 12 year old Collie mix a flea bath found 5 dead ones, so I throw out her blanket, use her treatment like a week early and bomb my apt,all in the same day put flea carpet and vacuum every day. I think they are outside, in the same area where they put Sandford and Son put all of there boxes. So I wait 2 days another bath and find 2 dead fleas. Now tomorrow the apt complex is bombing all 3 apt. But when I brushed her tonight I found 1 on her, but a bald spot near her tail and her skin is really dry. I heard vegetable oil in her water and another bath? I'm calling the vet in the morning. Thanks