Sum If Function

I'm about done on my first build using Quickbase, I'm looking for something similar to a sumif function where I can summarize a sequence of number fields on a record where I only want to add up numbers greater than zero.

There is a sum function and I tried the following without any luck.  

sum(if([Change Stucco Price]>0,
[Change Stone Price]>0,
[Change Lap Price]>0,
[Change B&B Price]>0,
[Change Shake Price]>0,
[Change Shutter Price]>0,
[Change Corbel Price]>0,
[Change Soffit Total Price]>0,
[Change Gutter Price]>0,
[Change Plaster Foundation Price]>0,

([Change Stucco Price]+[Change Stone Price]+[Change Lap Price]+[Change B&B Price]+[Change Shake Price]+[Change Shutter Price]+[Change Corbel Price]+[Change Soffit Total Price]+[Change Gutter Price]+[Change Plaster Foundation Price]),
0))

I know that this formula doesn't work, but figured I would put it here to give an idea of what I'm looking to accomplish.

Any help is appreciated.

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Paul Elliott
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