You can roll your own and not have it be associated with you if you lease third party server space and install your VPN set up on that server. For example, Amazon Web Service - pay for some of the bandwidth and you have your own computer in the cloud to serve as your exit point. You will then VPN into that leased server and have all of your outbound traffic exit from that AWS server.
You would have to lease the virtual server using a pseudonym and pay for it anonymously (privacy.com, prepaid cards, etc).
I do not recommend this route, even if you are very experienced, because you’ll be responsible for patching the virtual server and maintaining it. Although if you already had the skills to do it, you wouldn’t be asking how to do it. It’s much cheaper to drop $40/year or less on PIA and be done with it.