An alternative is looking at unused spaces and seeing what can be made out of them. For example there are several spots under the westway that are sheltered, streetlit and smoothly surfaced. They would require work/maintenance but you could 'own' the space easily enough. Indoor spaces can also be fairly easily accessed if you're interested enough - for example we used to skate an abandoned car showroom that had a marble floor. Imagine that as a polo court...
An alternative is looking at unused spaces and seeing what can be made out of them. For example there are several spots under the westway that are sheltered, streetlit and smoothly surfaced. They would require work/maintenance but you could 'own' the space easily enough. Indoor spaces can also be fairly easily accessed if you're interested enough - for example we used to skate an abandoned car showroom that had a marble floor. Imagine that as a polo court...