Exhibition design

Exhibition Design help needed

I am a product designer and I have also designed a few exhibition booths at my current office. I have now been asked to freelance a small booth. The perspective client is new upscale urban clothing company.

I will only be doing the design work (no construction) and I am not sure if i should charge a flat rate or per hour rate. I plan on showing a round of sketches, then final (2 concepts) then some final renderings.
This will most likely be a 10x10 booth

If i do per hour, how much should I charge? Whats an average flat rate fee for exhibition design of this size?

Thanks

How much experience do you have designing exhibits?

Is there a time limit (time frame) to this project?

Would they do ALL the communications with the manufacturer?

i have designed and built 2 custom booths. So I guess I am by no means a pro. Yeah there is a pretty tight time limit, about a few weeks. They are doing all communication with the manufacturer.

Maybe 1K-1.3K per week/ or $200-$300 a day!