Thanks to you and all the others who replied to my 'hello' . It's very encouraging and reassuring to get this feedback from everyone on their experiences. On the last house we had a difficult site (1 in 4 slope with very tight access) with lovely views, south facing in Guildford. It was therefore an expensive build not least because we had to do a lot of drains work and retaining. We had an excellent builder but very few people now much about ASHP, MVHR etc and in particular integrating all the systems for maximum benefit/ minimum cost. We were all electric. It took me about 9 months to get it settled down. We were making about £1400 a year from FIT payments, we got in at the absolute peak and the cost of power for the house was about £100 a month so we were fine. We had a lot of south facing double glazed window so it isn't environmentally first class but we had a calculated SAP of 82 and the EPC when we sold it came out at B not bad for 320 sq.m. detached in an exposed position.
The hob thing is interesting and we have talked about a gas ring partly to heat an empty pan but it seems that some modern induction hobs can handle this.
We are finalising the design at the moment and will for for a pre-app during January . Depending on this and the neighbours reaction we'll move to detailed design after that. Our daughter is doing a big extension nearby over the summer so we may not start until late 2018 as it will give us a chance to look at her subbies... and get the heating and hot water designs as simple as possible.
I agree with you re MBC and the foundations. We went to see them and we were impressed.
all the best