Paying for design decisions

[Alisha Zwirtz]

Attempting to hammer out how to pay the different team members involved in a flip. Our designer will be responsible for choosing all 'finishing' items such as paint colors, lights, countertops, doors, sinks, faucets etc. We will provide the material list with expected cost- they are responsible to stay in budget. 

The hope is that as time goes by this list will become more standard, but currently it is a blank slate. 

Is it recommended to pay by the hour or a flat fee? How much? Thanks so much!