@Marlene *****
You should be able to get non-O (marriage or volunteer) in your home country. But non-O (retirement) depends on which country. For example, USA: "yes"; Australia: I think "no".
I think these are all 90-day visas. You do not have to do any border run when extending. Once you have arrived on such a visa, it is just the same as if you had obtained it inside Thailand. i.e. you can easily extend it every 12 months.
There is(was) another type of O-visa (marriage) that was obtainable in Savannaket and HCMC that was a one-year visa with 90-day stay each time. So that visa pretty-much required a border run every 90 days.