We are in the early stages of a self build project. Planning has been granted, we've selected our timber frame company, and are close to submitting our building warrant. The less said about fees, engineers and architects the better 
.
However I'm starting to look into details now, everything from heating systems to bathroom tiles. There's so much to decide on. Has anyone else done it, or in the middle of it? Any top tips for how to approach so many decisions at once? Learnings along the way? Pitfalls? Where to spend money vs save. I have a billion questions, really, but thought I'd just start generally! Meanwhile I'm reading other threads here and elsewhere to glean advice.