Petco, most pet stores, train their employees very poorly sometimes. If you go in you might get someone who knows what they are doing or you might not. You might get someone who is afraid of birds even. A bad clip can be dangerous for a bird. You may just need to trim the first few feathers at the outside point of the wings, only the ends of the primaries and not any of the secondary feathers, it depends on how well your bird can fly. You can do it much more safely for the bird than they can, and it isn't hard. It doesn't hurt them. Nails maybe I'd get them done at a vets and then use a grooming perch or two, read up on them here because using them incorrectly can be hard on the feat, but with proper perches the nails will stay at an appropriate length, the way they do in the wild. I've read about birds dying during beak trims, maybe the tech held the Dremel incorrectly and sprayed dust into the birds lungs? Never allow your bird to be taken to another room away from you - you must stay with them and trust your instincts if something doesn't feel right. An inexperienced tech can crush a bird or frighten them badly or otherwise injure them. A bird screaming because he's mad or alarmed is one thing, but a bird screaming in pain and terror means do something.