Well....the other advice here is good regarding marketing your development at the stage it's at now. However, you asked about pre-construction.
It's way too late to market pre-construction. Pre-construction means before construction. You say the units will be completed in the next few months. When I see pre-construction deals, there's just the land and plans. And even if that's where you are right now, gearing up a marketing program takes time. Laurie makes a good point: People like to be first. That's the sell of pre-construction, as well as getting in at a lower price than the post-construction buyers.
Also, your web site needs a lot of work. If anything, it's working against you, not for you. Here are just a few of the things I saw: It uses builder/commercial terminology, not consumer-friendly promotional language. For instance: "Pre Construction Deals Starting @ $258 for 2 Bedroom 2 Baths." We won't quibble over whether it's preconstruction or not. But it's either "preconstruction" or "pre-construction." Not two words. Then you use "Deals." A used car salesman offers me a deal. Someone selling me a house for a quarter million dollars doesn't offer deals. The use of "@" is way too casual for your audience. And it's either "2 Bedrooms 2 Baths" or a "2 Bedroom 2 Bath" home. Not singular bedroom and plural baths.
You list "Unit Amenities" and note that washers/dryers come in "every unit" and that there are porches or decks with "Many units." Mike: People don't buy "units." They buy homes.
Those are just a few examples of terminology problems.
Then there's poor text formatting on the site. Small example: The listing for the phone and fax numbers at the bottom left of the home page: "ph. : (201)- 488-4455 fax (201)-488- 8280" "Ph" has a colon after it; "fax" doesn't. Phone numbers aren't written with a dash after the close parens on the area code. You've got a space before the "8280" on the fax number. It just looks sloppy.
On your "Residences" page, you have floor plans, buy they're way too tiny to read. A user should be able to click on them and go to another page with a full-page floor plan, or a PDF download.
Get a different mortgage calculator. The one you're using has a bunch of problems. First, it's not clear when entering an interest rate whether one should enter a "6" or "6%" or ".06." Plus, I'd suggest a default value in there that people can overwrite. Hey, people don't know whether today's interest rate is 5%, or 6%, or 7%. You're making it more difficult for some of them to plug in the "right" number. The results aren't formatted. And, worst of all, don't show people what they'll actually be spending over the life of the mortgage. That will scare them off. And because few people stay in a home for 30 years (or 15, or whatever), it's not really relevant, either. What they want to know are their monthly payments. And speaking of monthly payments, the calculator says "monthly payments," but the real monthly payments, including taxes, insurance, and any homeowner fees, will be higher. It should make that clear.
The units appear to be duplexes, at least from the tiny floor plans. If they are, this ought to be made clear. Otherwise, buyers may think they're buying single-family homes.
There's a bad link on your "Sign Up" page. It reads: "Click Here to get directions." If you click there (oh, and "Here" should be lower case, not capitalized), you're taken to an "Admin Login" page, not to the directions.
The "Sign Up" form has all sorts of problems, too. "Callme" is not one word. You have "How Did You Hear About Us?" in all initial caps (incorrect), but "Will you need financing?" in proper case. Speaking of which, do you even need to ask "Will you need financing?" You're trying to get people to express interest; at this point, their need for financing is irrelevant. And you ask "Income." That's a question that some people are reluctant to answer...especially online, at a non-secure site, communicating to someone they don't know. Leave that off; it's depressing your response.
And you refer in your question, and on your site, to a "luxury" development. Maybe standards are different in Wappingers Falls, but in the DC area, what you're offering doesn't sound like luxury at all. OK...stainless steel appliances. At least that's an upgrade. But carpeting on the second floor; that's cheap, not luxurious. Central air conditioning? As opposed to what: window units? Washer/dryer in every unit? Let me guess: probably a stacked unit. Dishwasher? That doesn't elevate a unit to "luxury."
OK: Some general advice. Sell the sizzle, not (just) the steak. Write the copy for prospective purchasers. Make the images consistent with the description (of luxury). To try to sell them quick--beyond the good advice provided by others here--try to generate a sense of excitement, exclusivity, and limited availability. And do research on your target customers, then market heavily to them.