Auctions are great places to find garden and patio furniture and old pots with lots of character to plant a grouping of flowers. Patios are well suited to wonderfully designed metal furniture that adds so much more character than what you might buy from Pottery Barn. This lovely French patio combines the old metal furniture and some nice old pots in the background.
Art et Decoration, France
Auctions are full of options for urns and you might plant it like this.
Both from Traditional Home
Another idea would be to position a decorative metal bench facing an interesting ornament to create a small 'room' in your garden. Even if you never sit there (but you will) it's a great visual from elsewhere in the garden or the house.
Stair Galleries in Hudson NY had some great examples of things at their last auction you might put in your garden or on your patio (or balcony if you have one in the City).
The urn on the left sold for $225 and the cast iron urn on the right sold for $300. The first would be a wonderful focal point, while the second would look great with flowers arranged in it as in the picture above.
This zinc bath really intrigued us and we were sorry not to have bid on it. It would look great at the end of a garden vista planted with lots of flowers and greenery.
This ended up selling for $175! it might have cost more than that to move it!!
Here is a picture from Traditional Home on arranging an outdoor dining area that I love, including the chandelier hanging from the trellis!
It's a wonderful 'room' in the garden, and auctions would offer all sorts of opportunities to replicate.