[dad911]

I would never go for a percentage of costs. There is no incentive for architect to save you money, it will be in his best interest to over-design all structure & finishes, etc... Plus, if you upgrade granite/cabinets/appliances/tile... the 'big ticket items' there is no additional work for the architect.

I pay by the square foot for new plans/new construction, but that is totally different.

Having said that, a good architect can easily save you money. Try to get recommendations.

You should be able to scope out the work, and get a fixed price. Be sure ask about addition costs like as-builts and field changes.