OK, call it a half day (four hours) a month.
But really, if DIY, someone's got to actually have it meet SLOs and SLAs. So you need a person or two, which is when those hours add up.
These days housing and benefiting an employee can cost 50% to 100% overhead, depending on firm efficiency. So, $400/hr means $800k/yr (because 40 hrs x 50 weeks = rate x 2000) but half that can be considered overhead (recruiting, real estate, benefits, training, vacation, "management" when some number of headcount requires adding a lead or manager who is expensive overhead), so it's really 400k a year which is not out of line at firms with regulatory requirements.
Anyway, if your workload is critical, you can't have only one, so call it 2 at 200k. Point is, when all these things matter, GCP/Azure/AWS isn't the thing that stands out.
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> As the rest of your comment, personally, I see it more like a pitch to use AWS
Re AWS, I thought I was clear:
If YAGNI, don't choose it.