I think sometimes reading the buyers feedback comments is useful even though they may be showing 100% feedback. Buyer positive feedback happens because sellers are not allowed to give negative feedback - ebay rules! Forewarned is forearmed.

What you can do as a seller is just make sure your TOS (Terms of Sale) are very clear and your descriptions and photos of items are thorough honest and accurate. Add to that you do not pay return postage on items and be clear about any returns policy you have or don't have. You can also block previously difficult buyers from bidding on your items. You can also check if they have retracted previous bids on similar items. 

Just a few thoughts on your current listing

1. I would show a photo close up of the pattern - you can't see it from the photos you've posted - and another of the cracked teapot lid.

2. I would change 'collection preferred' to collection only, or

3. I would not offer to deliver unless it's FOC within say a 20 mile radius of where you live.

Otherwise how are you going to charge if the person lives in Devon?! You have to do the thinking in advance for your buyers...

If people don't want to collect it themselves then suggest they use a courier of THEIR choice, unless you can offer the services of one who you know to be reliable. If you do that though you're going to have to pack it all up!

4. I would be inclined to split the existing listing into 3 listings...

One for the tea service, one for the coffee service and one for the dinner service but that's just my personal viewpoint. The 'cup cake' and the Great British Bake off" have encouraged people to use tea sets again but they might not want a dinner service. 

Just realised I've probably been a bit presumptious in offering you my views on selling, so do please forgive me as my enthusiasm runs away with me sometimes.