With that said, since I have seen good ROI for certain businesses on advertising spend, we are eyeballing their 'Enhanced' Listing Service. For $75/month it blocks all competitor ads on your page, let's you control the order of your photos, and lets you create a call to action button. They claim 38% more leads. Haha, I'd like to see an unbiased third party verification of that number. My marketing gut feel on this is an add-on rip-off, but if you're a business that gets thousands in sales from Yelp leads, even if it increased your leads 10% the $75 is insignificant (I'm sure Yelp wants us all to think that way too.) That actually points out a major flaw in their pricing model, it's the same no matter what type and size of business it is. because it's not an auction format or a cost per converstion (aka cost per aquisition CPA) model that has varying rates depending on the business category. So their too expensive for some, and leaving money on the table with other more lucrative business categories. But that's their problem.
So let's examine the features of the add-ons.
Block competitor ads - To me this is really only beneficial if you have a much weaker review profile (in number and average score) than many of your competitors. If you are already one of the top businesses in your category with many 5-star reviews, people are still going to inquire whether there's an ad for your competitor or not. This *might* though have an effect on your ultimate conversion rate as it may lend itself to making people shop more companies if they see ads to competitors but I would say the effect is probably very negligible.
Photo Ordering - Nice to have that control but it's only going to have a benefit if users have uploaded tons of photos. If the only photos on their are the ones you uploaded, then having this control offers no significant benefit in my opinion.
Call to Action - Finding the button or link to contact the business isn't difficult. Again, benefit on this is questionable.