Whoa, whoa,
First, sure I know where Manoguayabo is although I can't tell you excatly and technically where it stop and starts.
Second, if you have to ask where it is, you aren't even nearly ready to buy property there.
It is indeed on the far west side of Santo Domingo just west of Herrerra. Generally speaking it is a fairly poor area similar to Herrera. I am not sure, but there might be a few decent develpments that would be considered part of Manoguayabo although I think anything under that category would be considered to be in Herrera. Generally, for most of us, it would be an area to avoid.