Well obviously the more you do yourself,the less it is going to cost,try to find a tradesman by word of mouth,explain works required
To get a tradesman to work with you and for him to agree to let you hang rads and lift floor boards ect to save on costs,I would say you should be aware of the following
1...Do not mess him about,if you are going to do something ,do it,this is why we do not like customers helping out because 9 times out of 10 they say they will do something and do,nt
You go to a job and agree a price ,as customer says will hang rads and lift agreed floor boards and you get there and half the rads not hung and one floor board up,that was loose anyway,they come up with all excuses,so tradesman ends up doing it all and then want it done for the same price or a fraction more
2.Plan things out,if you required new heating system,then also replumb,maybe ,rewire two,when you have floor boards up,get as much done as possible
plan all positions of required items ,rads,sockets ect,extras cost a lot more to do than if done following original plan,and plan for future if you are thinking of loft conversion or extension, get cables and pipeing to a point they can easily be picked up at in future n the right sizes to be required
3,Profit is not a dirty word and that is why we all go to work,you will be saving by doing a lot of your own works,do not try to cut into the tradesmans honest profit,all that will happen is they will take short cuts,become unrealiable and maybe move to other works
I have done a few bigger jobs working with customers doing what they can,some have gone great,as we have been straight with one another but a few ,the customer could not do what they said and taking the micky.... exit stage left...can cost me to much money being messed about
As for system would be looking at a system boiler with unvented cylinder,will keep all the family happy,warm and clean