Rendering price strategy and structure

In a bit of a bind here…I’m not looking to find out about anyone’s pricing rates. But I do have a bit of predicament pricing out a certain level of work. My pricing experience goes into creating an out lined proposal for a full scope of design work from soup to nuts (ID to Eng). I’ve recently received a request for some very specific modeling and rendering work for presentation purposes, that’s it. Since I have no experience in this realm and I would like to retain this client, I would like to know what other people’s strategy is for submitting a quote for a simple housewares type model and rendering. Mind you, in the end, I don’t even have to submit a written proposal, just an email with a price. I’m also pretty sure I’m not competing with anyone else on this job…All thoughts are welcome…

I’d just estimate an hourly amount for each one, give some % buffer and quote that per image.