When I was lowballing bids to get projects, I bid out a project at around 700 dollars if I remember right. These guys had a site that they wanted to enable doctors that were studying for the MCAT to get flash cards. It was a great idea, and I had a way to handle the flash card piece of it already thought through. I got going on the basic layout and theme, and these guys got so picky in every single detail of the CSS, it was a huge mess. We had agreed on a soft estimate for the cost of the site, but I was still charging them hourly. I explained to them a couple times they were being so picky on the CSS that it was blowing through more hours than I had estimated. This was before the days of really easy css frameworks, so I didn't have that luxury.
It ended up blowing up the project because they didn't have enough money to push through the project, but also didn't want to give up on the nit picky css details. So when they ran out of money, I handed over a half finished project, and no one was happy. Really sucked.