I don't have physical access to my witness server, since my internet connection is not reliable and/or fast enough (I have a 20/5 Mbps connection with a 300 GB/month limit (it's capped at 5/1 Mbps after)) to run it at home.

If something extreme happened and I couldn't host my witness at any server provider, I could get a witness up and running on my personal PC in under 3 hours, and I could get my own hardware & better internet connection in about 1-2 weeks.

But unless something really extreme happens, I prefer renting servers since it's much faster to upgrade/switch to a new provider and they have more reliable power/internet than most households (and it's cheaper).