^ This exactly. A half-decent used Thinkpad can be picked up for slightly north of $120. And it will have 4-8x RAM and at least 4-5x CPU performance. And you own it! The only thing you potentially miss out on is: uptime SLAs ("reliability") and a higher-speed internet connection.
You also might miss out on a public IPv4 address, but that's whole 'nother issue... FRP (fast reverse proxy) is a decent workaround for this.
Now take into account electricity costs. Where I live, running a Lenovo constantly @10w for a year would cost me $30. Then you avg the remaining lifetime of your laptop (5yrs) and the time you spent setting it up and you will find out, a $5 droplet is a cheaper option ;-)
Fair point, it depends on your workload a lot. If you're hosting a few static sites, a droplet _might_ be a better option. Previously, I was paying an arm and a leg for $90 worth of droplets a month to cope with my remote-compile applications. Plus, I don't pay for electricity at my current apartment. It's included in my rent, so I'm really paying for the electricity whether or not I use it (within limits).
You also might miss out on a public IPv4 address, but that's whole 'nother issue... FRP (fast reverse proxy) is a decent workaround for this.