Sorry op if you’re being serious, you don’t need to take his word for it, not at all, you can look at the picture and make your own mind up like everyone else,
if the pair of you like that and want it in your garden and to sit under it, and can’t knock it up yourselves, for whatever reason, fhen just email the organisers and ask. They will be able to tell quickly.
Or contact a local carpenter , he or she would be able to knock it up quickly and cheaply, plus source sone rusty corrugated iron for you both.
it’s very like our overflow wood store my husband and his brother built, took them about a day, wasn’t a big job, but they had to cut all the wood to size etc, The only difference is the roof on ours is green corrugated bitumen as we wanted it to blend in, rusty corrugated iron isn’t our thing, but we all have different tastes, and I’d clearly not consider sitting under it..🤷♀️
anyway, ask the organisers or contact a local carpenter.