Greetings,
My neighbor and I purchased all new Trojan Batteries at Price Mart about 5 years ago. Turned out they were a "defective batch" and all of mine, and his failed in less than a year. I am not saying this is going to happen to you today, but at 1K US, an 8 battery bank X 2 = mucho pesos! I think it was around the time the price of lead was going through the roof and to stay competitive, Trojan decreased the amount of lead in their batts. (I read about this someplace at the time). To make a long story short, I purchased all new batts at TRACE in POP. They also have a store in STI. The reason is that the batts are just as good and TRACE offers a warrantee which is RARE for anything in this country. I had one battery fail in the first 4 months and they came out and replaced in for free. The warrantee does not last forever, however they do "pre-rate" the costs over time. You have to talked to them about that. Also I would suggest you have them do the installation. Its helps. They also warrantee their inverters. I had been hit by lightning twice at different time and twice they gave me a new one for nothing. Other times over 8 years they will do the repairs if required and a discounted price over time. They also offer "service plans" for a price. I have not engaged in that though. You mileage may vary but I suggest it is something to check out. Respectfully.