That will depend on your passport country. If you buy a tourist visa then you can stay for 60 days. For most countries you can extend that once for 30 days. If your passport country allows a visa exempt entry then you can indeed do a “border bounce” and come in for another 30 days, and can get one extension off of that.
The evisa system doesn’t allow for a multiple entry Non O visa. The non OA visa does not have two options. There is only one. It’s a year long multiple entry visa.
The re-entry permit is a different thing all together. That permit keeps your “allowed to stay” date alive should you wish to leave and return to Thailand.
I don’t believe there is any consulate in the world that will sell you a multiple entry Non O based on retirement. A couple of them will based on marriage.