As you are in my area, I can speak for the Houston market,. Other parts of the country and state handle title differently. As stated by other professionals in our area, this is a negotiable item but is usually picked up by the seller. The exception to this is new construction where the builder will expect this to be a buyer expense unless they are offering an incentive to cover this expense (usually tied to the buyer working with their recommended lender, who is often owned wholly or partially by the builder itself). So in theory, a seller who sells his/her existing home and buys a new construction home could end up paying for the title policy on both. This is yet another reason that an expert Realtor can help wade through the technical issues and save their clients a lot of money by understanding title and other issues and how they affect the client's bottom line.
In all of my years in this business, I have had one buyer pay for it on a resale listing. This is because we had 5 offers in the first week on the market and this particular buyer had a company relocation package that paid for his closing costs and he was able to offer the best terms to our seller. Otherwise, my sellers have all paid this fee and we usually structure it in the asking price of the home, as we do all closing costs. In the end, it really is the buyer who pays for it in the sales price but that is another story. These title policy costs are regulated by the State of Texas and standard from company to company. Hope that helps.