Greg -
The requirements for renewing a 405 visa can be found at
http://www.immi.gov.au/visitor...405/how-to-apply.htm.
In particular there is a Document Checklist specifically for renewal at
http://www.immi.gov.au/visitor...hecklist-renewal.pdf.
I personally doubt that you would get away with using your returned $250,000 from your initial Designated Investment as a means of displaying an income spread over four years. You would be using capital, not income - which does not meet the DIAC intent of proving ongoing income.
Besides, this would only last you for the duration of your first renewal. Assuming you want to stay here after 8 years, you would again have to prove you would have an income of $50,000 per annum (not $55,000 by the way) for years 9-12. There would be no capital returned to you at this second renewal - the remaining $250,000 has to continue to be invested for the rest of your stay in Australia.
No you don't need to show any settlement funds this time - after all, you have already settled here, haven't you?
There is no need for any health check for the vast majority of people. At application you can assume that you won't need anything, and DIAC will review your travel outside Australia to see if you have been anywhere that might pose a health risk. Only if they see such a risk will you be asked to undergo certain checks.
As far as "criminal checks" are concerned you will definitely need an Australian Federal Police check (see the Document Checklist for details). You will only need other checks if you have been in any one country for more than a cumulative 12 months since the issue of your last Police Check from that country. (Note that carefully - it is not 12 months since the issue of your visa - it is 12 months since your last police check. So you have to include any time spent in your home country after that police check and before you departed to Australia.)
You may not not be aware that some of us on 405 visas have an email circulation system where we exchange information and experiences, for the benefit of each other.
If you are interested in being added to that list (which currently includes 10-15% of all the 405 visa holders) please send me a private email. I control the circulation system.
I was the first person ever to renew a 405 visa and I posted an email on our 'system' to relate my experiences - including a breakdown of the total cost of about $21,500 to renew for two people. And that was before the annual increase which took place in July, adding another $365 or so to the total cost.
If you want to see a copy of that posting, then again send me a private email and I will forward it to you.
Regards,
Howard