Pre-engineered Building Foundation Engineering - Fee Estimate?

[onealexis]

How do you all estimate the fee for a foundation design for a pre-engineered building? For example, I have a pre-engineered building which is actually an addition adjacent to an existing building. The building is a total of 8200sf. It has 3 different framing configurations with two of those adjacent to the existing building. The contractor is 'designing his own slab' therefore I will design the foundations independent of the slab system (no hairpins). We have to design the foundations (concrete columns and footings) and the depth of embedment of anchor bolts. We are provided with the building manufacturer's reactions and anchor bolt plans.

The building is in New York.

To summarize:
Framing Config. A - main frame - outside columns with one line adjacent to the existing building (only 2' between existing building face and new column footings). This area also has one endwall with columns.
Framing Config. B - main frame columns with span twice the length of Config. A. Main frame columns all away from the existing building except for 1 column. 2 endwalls with columns - one of those sets of columns are adjacent to an existing building.
Framing Config. C - 'lean to' framing with an exterior line of columns with the greatest reactions.

If you would like to comment on what your actual design approach or procedure would be as well, feel free.