Is the HVAC system a dual or single system and what is it's tonnage rating?

The HVAC is a single system. Unknown of tonnage.

How old is the HVAC system?

Original Unit from year 2004. 

How much are the HOA dues?

$175 per month

What do the HOA dues cover?

  common grounds upkeep, access to pool, spa, Barbeque, front yard landscaping, front gate security maintenance

Is the Community Swimming Pool Salt water?

unknown