Legally, the US embassy has no say on who comes into the country.
As to signing a real estate contract in which the seller has no title, it is possible. However, in that case your lawyer should protect you from the possibility that title may not be obtained by delaying payment or setting up an escrow.
Quoting from my article on the purchase of real estate in the DR: (
http://www.drlawyer.com/txt/articlesreal.html):
“Real estate purchases in the Dominican Republic do not usually follow the North American pattern of a written offer tendered by the buyer to the seller, followed by the seller’s written acceptance. Instead, after verbal agreement is reached by the buyer and seller on the price, a binding Promise of Sale or Option to Purchase is prepared by an attorney or notary which is signed by both parties. A deposit or advance payment is normally paid at the signing of the Promise.
Many attorneys and notaries in the Dominican Republic do not protect the buyer adequately in the Promise of Sale. Among the most common deficiencies are the following:
• The buyer is allowed to pay a large percentage of the price of sale without any security or direct interest over the property. In case of misuse of these funds, the buyer’s remedies may be limited to suing the seller personally.
Many condo buyers in Santo Domingo have suffered through this experience in the last few years. Generally, the developer uses the buyers’ funds, along with a bank loan, to finance the construction. The bank collaterizes the loan with a mortgage over the property. When the developer misappropriates the funds or runs into financial difficulties, the bank forecloses and the buyers lose both their money and “their” property.
• Payments are not conditioned on the availability of clear title or the adequate progress of construction. Sellers, therefore, can demand payment or place the buyer into default despite the fact they may not have performed their basic obligations.
• Escrow agents are rarely used. The seller, therefore, has control over the funds as they are paid.”