Commercial photography can be rewarding so you want to make sure that you do a good job. I've turned down jobs that I didn't feel we could do and if you are honest with them many of them will give you a shot later when you feel you are ready.
There is a standard set of information that I must have before taking on the a commercial job. The most important is what is the end use which will drive licensing. The shooting part is easy to quote, it is either our daily rate or hourly rate if it is only a part day. Things like transportation, per diems, etc. all get added in. I have an excel spreadsheet that I use to calculate all of this. Did they give you a budget to work to, many will do that.
Quite honestly, if you don't know where to start on a project like this then maybe it would be time to turn it down until you feel like you are ready. The other option would be to contact someone that you know to help you with the shoot that has experience in doing commercial work. Was the contact from an agency or from the facility owner. If it is from an agency they are usually very specific in what they want and any advertising agency I have worked with will normally send along an art director to the shoot to ensure that they are getting what they want. Even if it is the owner of the facility it is their responsibility to give you clear directions on what they want and your responsibility to make sure you get it from them. I've done shoots for customers who give us a clean sheet of paper with no definitive directions. In this case we have them sign a letter of understanding that they have not provided direction and therefore anything that we supply has to be acceptable. Views, portrait or landscape, room for type to be set in a particular area, file size, color space and even file type are the questions you should have answered from the customer.
Is your 430 going to be enough light to get the job done. If I have to rent special equipment this gets added in subject to their concurrence but they also have an expectation that we will have the basic gear to get the job done. Only once have I had to rent additional lighting. Unless you have really small rooms, your 17-40 should cover it. Depending on the scene we will set the camera position and then do lighting changes across several images so that each component, lets say each wall for example, are lit properly and then we merge these together in Photoshop to get the best results. It is not HDR, though I know some that use this approach, but simply cutting and pasting all the pieces to get one good one. With any luck they would have a skylight so that you can use natural lighting which is always nice.
You must have an idea of what your time is worth and then add in any licensing and usage charges and you should be there. Of course you would have source yourself a licensing agreement for their signatures.