Scary prices.
I expect you'll have to pay landing fees on top of that £155/hour, at £25 a go, there's your train fare to Headcorn and back. Wait until you're doing circuits... £10, £10, £10 (train fare), £10, £10, £10 (train fare), £25 full stop (train fare).
Check the economics carefully before you make your decision, there are no landing fees at Headcorn.
I'm not biased, I did my training at Headcorn and now I pay through the nose to fly my own shareoplane at Biggin. I don't have a car either and travelled to Headcorn for my PPL from South East London on the train, but I don't pay (much) for the train, perk of the job.