Do NOT include the '.ampr.org' part of your name. This name must not be in the database already. For A type records this will be your IP number. This field should be the fully qualified name of the system execpting mail for your host. Note the use of DOTS at the end of these records.
Dedicated accounts cost extra money.
We know it's not 24 by 7. This is the argument you should use. Or at least this is the argument I use. I have two accounts. Every four hours my ISP hangs up on me and forces me to dial back.