Here are a couple to start with: I simply got these off the web so I have no idea how reputable they are but try them and see Bankers Title Corporation Parque Centro 1500 San Juan, PR 00918 787 * 753 * 0339 Efrain Tirado Appraisal Group P S C 1431 Avenue Ponce De Leon 801 San Juan, PR 00907 Estudios De Titulo Ana Echevarria Investigacion 102 Torres San Crst 204 Ponce, PR 00780 Finca Galateo Limited Partnership 207 Calle Tetuan San Juan, PR 00901 Garcia Andres Rivera 555 Prira Leal Street Apartment 201 San Juan, PR 00923 787   531-1179 Ocean Park L P 207 Calle Tetuan San Juan, PR 00901 San Juan Abstract Seguro Titulos 259 Calle Chile San Juan, PR 00917 William Negron Quinones 402 Calle 2 San Juan, PR 00923

That being said, to me it sounds like the initial $670 fee you were charged was the " Initial Deposit" Here in PR ( and many places in the states as well) lenders charge a fee once you are under contract on a property to cover the initial expenses such as the Appraisal, Plot Plan ( in PR these are mini-surveys on single and multi-family homes), and the Estudio de Titulo ( title search). 

@Juan BravoCheck out the people @Dennis Rodriguez mentions.If a bank won't be involved, make sure you do a title search ("Estudio de Titulo"), make sure property taxes are paid and I would get Title Insurance (just to be safe and it's cheap).I don't know about any specific problems/issues/concerns with the owner financing part.