I don't know if this qualifies as a house project. but my veggie garden is ~10-15 feet of elevation above my garden hose spigot. My understanding is that I would theoretically need a very expensive backflow preventer if I was to pressurize a line up to the garden, and I don't have a convenient way of burying a line anyway. I'm getting a little too worn down to lug 5-10 gallons of water uphill.
Plan 1 was to put a rain barrel at the top of the hill with a rainsaucer...but the rainsaucer company went out of business a few years ago and I haven't found a suitable alternative.
Plan 2 is to put a bucket at the top of the hill and use my hose sprayer to fill it from a distance. Won't be super accurate, but it doesn't have to be!
My first reaction is like you, put in a rain barrel. Then maybe you could put in one of those perforated hoses, and you can just stick a 1/4 turn valve in the base of the rain barrel and you could just manage the valve when you want to water it?
I'm on board with the rain barrel concept - and I think if I raised it a couple of feet above the elevation of the garden, it would generate decent pressure sticking a valve at the bottom. Would need to do some math about the pressure needed to feed drip lines. But if I'm not mistaken, rain barrels generally feed from gutters that feed from a roof. I need something wider, which is where the RainSaucer concept came in. Maybe I could DIY something out of a tarp.