I'd never waste time making my push mower look pretty

Patio Chairs/tables I'm OK with rattlecans. What I had in mind when I posted was car parts. Engine brackets, valve covers, suspension parts, etc. Parts that will likely see fuel, oil, dirt, rocks. Parts that I'd be periodically cleaning to keep them clean. In my experience rattlecan paint is just generally soft and less durable. Bump a bracket with a wrench while working on the car and the part that I spent time prepping/painting has a nice scrape in it
Another application that I had in mind was painting cosmetic parts for my boat, where I want a high-quality finish that will stand up to the elements. I had an upcoming project to do some repair and refreshing on my dashboard, including some fiberglass work. No way I was going to just rattle-can that. If anyone is interested, I ended up using a 1-part roll/brush-on urethane paint from interlux and I'm thrilled with the results.
Interlux Brightside
It's pricey at about $50/quart, but it flow out incredibly smooth, has a great gloss, and should be plenty durable given that it's intended for marine applications. I'm curious if anyone has experience with a similar non-marine grade product that might be less pricey.