Congrats on the house, best advise I can give you is, build relationships with local tradesmen if you already haven't. This will save you so much time and money in the long run..
Brought my first house 14 years ago and was completely ripped off by tradesmen to begin with, a couple of months and a few pints later the prices went down by 20%..
Not sure on the boiler thing, I always call my brother out to do stuff like this for me...
