Some thoughts from a very ancient gardener, which might be useful to someone. I have had several rotary washing lines from the recycling centre over the years but always dismantle mine and make stakes and plant supports with the arms as they are so robust. Recently bolted three metal arms across two longer ones to make a trellis for a climbing rose. The stakes last for years. Large patio umbrellas can also be dismantled and used for the same purpose.
The other wonderful and indispensable items usually found at recycling centres, are gazebos - the lightweight ones usually used for a one off event. The poles slot into each other so can be used as frames for brassica or carrot mesh & are much cheaper than versions found online or in garden centres. These can also be extended as plants grow. Plastic corner pieces to join the poles together can be found online or at some garden centres and the gazebo covers make lightweight tarpaulins.
Finally, I make supports for my peas with 6ft or 8ft stakes. Square 5ft or 6ft mesh pigeon netting, the knotted not woven sort, is measured to the length of the bed and stapled tightly to each of the stakes which are then driven in each end of the row. String or a cane is woven through the mesh top and bottom and tied to the stakes to keep the netting taught. When the peas finish, the stakes and netting can be rolled up and stored for the next year. This form of netting doesn’t tangle like some of the nylon types do & lasts for years. If the peas are very vigorous, string tied from one stake to the other just below the tops of the plants will hold the plants to the mesh & encourage them to climb.
Hope someone will find this useful, has certainly worked for me over the years.