There is a hidden cost to every hobby and everybody is willing to tolerate a certain degree of shittyness.

I have a friends that has a rather old car and something on it is always broken. But he has no problem having 20 different apps for appliances, instead of deploying home assistants. Or having ads everywhere and even trying pihole or at least NextDNS.

On the other hand, I see my car as a transportation tool and when I need it I want to use it without worrying about some random part exploding. But I have no problem running Proxmox and hosting tons of services for my family.

That said, I would definitely not self-host something like NextCloud or any business critical component for my business and just paid somebody for the service.

Take what you have, start small and learn from it.

Old laptops are great, because they have low power consumption and even pretty used up battery will give you power redundancy.

Even a 10yo laptop is something with 4-5th gen Core cpu and that has plenty of power to get you started.