NT properties in the SE (or further!) that are accessible by public transport

[BornToFolk]

My mum very kindly bought me membership of the National Trust for my birthday and I've been looking for places to go. However, lots of them are tricky to get to without a car and it's hard to search for which are easy to get to by train/bus so I was hoping people had some recommendations?

We're in Reading, so well linked by train and I'd like places that take no more than 2 hours to get to, so we can do them in a day. We went to Ham House last year and really enjoyed it.

I live near Sevenoaks. You can take the train to Sevenoaks station and I believe there is a red bus that takes you to Knole House and Deer Park. If that is not running it is a walk up a steep hill to the town centre. Knole is the other side of the town so would be at least 15-20 mins walk.

Dapdune Wharf in Guildford isn't very far to walk from Guildford Station. I think both Hatchlands and Clandon house are accessible via train to Guildford and then Bus.
I think it you go to the NT website they give you ideas for transport.
There are a few places in London, and other places you can visit with a discount - they should be in the guide book.

If you don't mind changing trains then you could get to Poole in just under 2 hours and catch the ferry to Brownsea Island. It's only open March-November at the moment though.

Thanks for the suggestions! These look great!