Kind of a hard question to answer as there are lots of things that would still need to be answered. Are they requiring you to blow out cornors? Are thry requiring you to haul away debris? or do they have a dumpster ther for you to use to dump in? Are they requiring it to be done daytime or night time? Will there be cars in garage when you are completing the job? Is there a noise ordinence that you have to deal with? All of these are factors that need to be addressed. But after you have these answers you just need to figure out how long it will take you to complete the job and multiply by your hourly price. If you cant make money,,,, what is the point in having it. There are lowballers everywhere,,,,,Let them have it if you arnt making money. Plus you dont want to get into a problem with the " you were supposed to include that " " now I want you to do that also and not change your price " Make sure your contract spells out exactly what you are doing for the price you charge them.
Hope that helps a little.