Please be aware that there is a new domain name scam being undertaken by a company called Domain Registry of America (DROA).
This one is slightly different in that they send you an invoice first then a few days later try and transfer the domain to themselves.
This is a blatant scam committed by a company you should not want your domain to be managed by. If you get one of these, give us a call on (08) 8219 9925.