You may well be plagued by negative energy, but the way this scam works, once you fork over the $3,500 there will be some other problem that is even more urgent that requires even more financial investment.
Instead of doing that, why don't you try meditation. Pema Chodron is a wonderful author who write about people plagued by bad stuff. If you live near a buddhist center in this school of Buddhism, they'll teach you to meditate for nothing and you can learn to transform that negativity yourself.
All the best to you, Corkhead. Hang in there.