Coverage for pre-existing condition - Is it available ?

Has anyone ever succeeded in obtaining a visitor's health plan that covers pre-existing condition in any way (Even if the coverage is limited to a certain amount ) ? I had spoken with an agent who advertised that such plans are available. he quaoted me rates ranging from $3000 and $5000 PER MONTH !!!! if i could afford to pay that amount as premium, why would i buy an insurance policy ?