Architect / Engineer to redraw small building and generate project material estimate

Hi

I am looking for someone with Architectural / Structural Engineering experience to adjust and redraw this small house I am building in the Caribbean. (so that i have proper drawings for the builders)

It is already drawn in simple form and available in 2d 3d render and CAD. (see some examples below)

What I want is for it to be 'tuned' / adjusted slightly dimensionally etc so that it accurately represents something simple and cheap to build...it will be of 8'x16' block-work and concrete floors and roof so the dimensions of the design should be to fit with the blocks etc, and also to add the foundation, concrete support lintels etc.

Then I need a project quantities estimate (obviously the design software provides this but i haven't drawn it accurately enough)

The design is in ft/inches etc as that is what they still use there.

I need this to be done quite quickly but will be straightforward for someone with more experience than myself.

Many Thanks Chris