Bungalow Roof Lift - Potential Floor Plans

[Cheesus]

Hi all, we are in the process of looking to rennovate a 2 bedroom bungalow to incorporate an annex/granny flat plus a roof lift. We have just started with very rough sketching prior to appointing an architect and this is what we have so far (we need to add a staircase). We are considering having a vaulted ceiling over the end of the living/dining room but this would depend on cost and if we can accomodate a bedroom, dressing room and house bathroom upstairs plus the steps. 

 

The annex would be self contained to the left. The first rough draft of the downstairs floor plan is below (measurements are approximate at the moment but the gist of it is hopefully clear). Does anybody have any input on what we have done so far please and any comments on how to design the upstairs including steps? 

 

We're hoping to give the architect as much to go on as possible. 

 

Thanks.