Point me to one case, just one case, where someone has been deported and banned for a 'very long' time for using an agent to get a retirement visa. Or, indeed, a case where an immigration official has asked to see the bank book of someone with a retirement visa acquired using an agent.
The exact requirements are all listed on all embassy sites. Yes, it is acceptable- Rapid PCR is generally the only one that will come back in time. But you really are better checking all this on Embassy site.
Not if you don’t leave the airport (I think) but check with airline as they might have more up to date info. Restrictions have been relaxed in CNX recently
I thought you had to show proof of fully paid first month at least but, if you don't, or you can arrange to get refund of that, I don't see why not, as long as you log a new TM30.