Having the right agent with you is key when shopping for new construction, and is here to help you navigate through your options in the Tampa area.
Buyers of brand new homes in a neighborhood don't like to see houses sold after theirs go for less money, so builders aren't as apt to bend on price. (You'll appreciate this behavior after you've bought a home in a development of new construction!) Regardless, depending on the market and the status of the project, there's sometimes room for negotiation.
For example, if a property has been on the market a long time and the builder is deeply invested, then you have some room. The same goes for show or model homes that have been sitting for a while. However, if a home was just finished, don't count on being able to get a deal.
You can always ask for assistance in other ways when purchasing new construction. For example, closing costs are one way for you to save without lowering the price of the house. The same goes for amenities - ask for things an allowance for window treatments, a garage door opener, a fence or landscaping, or an extended home warranty. That can go the other way around, too. If upgrades are already in the contract, try to get the builder to omit them - you might be able to install them later yourself at a savings anyway.
Realize that just because a house is brand new, it can still have its share of flaws. Be sure to get a home inspection before purchase so that issues are handled and also negotiate a home warranty. Then, about 10 or 11 months after purchase it's worth it to pay for an inspection and get anything else repaired before the warranty expires.