Aouca is WAYYY off from P.O.S
Depends on how much they are looking to spend. Right now real estate is crazy. It's pretty much jsut as expensive to build that it is to buy depending on the area.
Maraval and Diego Martin are ridiculously expensive and not that much space available. If they really want those areas, they will have to buy because there isn't much free land space to build on, everything is pretty much developed.
If you are thinking further east, Arouca Arima etc, there is more liklely a chance of buying land in order to build. There are a lot of residential communities now in the east. for the more pricey side, there is Trincity which has access to the biggest mall, golf course etc. Prices are really high and it's not as generous when it comes to space.
Furhter east, like Arima, there is a lot of land available. D'Abadie is a nice area where they can buy or build.
Chaguanas is a pretty good area to build also.
Pros and cons.... price doesn't really factor because they're both expensive!!
It more depends on the area they're looking at and how much space they want.
If they want to be accessible to P.O.S then they will have no choice but to buy because there is not really alot of land laying around like that. Land space in the city is more for commercial.
If they're looking for a nice spread... they will have to move further east (which i would prefer) or more central.
Also, they're a lot of gated communities now, alot in the east.
Good Luck :-)