I am sure that in ten years I would be happy with the appreciation and rent increases, but I need to be aggressive as I have limited time to build my monthly cash flow for retirement.

Get a partner to learn from and can compliment skills or resources you don't have (if you have money but limited skills, partner with a flipper; if you have skills and no money, partner with a money guy). 

In my leases, any hotel or other accommodation needs to be pre approved and states a $ limit per day and conditions under which it may be an option. 

The private flood policies usually won't pick up a property that has had a flood loss before, but a knowledgeable Nerd agent will look at all options to get the best coverage possible. @ Chris Happer you are absolutely right a Flood Cert (properly named (ELEVATION CERTIFICATE) can help with the rating for the NFIP (government) policy.

Germany has quiet hours and days which limit the majority of traffic.

Assume $1200 for below.Assuming I rent out only one unit (assume already rented) and the other unit is 'family rented' for $500, this gives me a loss of about $250/month, and not including repairs or vacancy loss (doubtful in this area even with 2 units available). 

I'm looking for a deal but as usual it has become harder every year with such limited inventory.

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

This isn't like California or NY where that would work due to limited space and expensive cost of living.

Individually you may get limited to the number of loans that the banks are willing to give each individual.