You sound like you need some advice about buying a motorcycle...
If you have never ridden, think hard, this may not be the best place to learn!
There are several different motorcycle-type options here, and you should think about where you are going to live and how long (distance) you will be riding it for. If you just want to get around a small or medium-sized town, why not buy a moped? Honda has some nice, reliable newer models. To travel a little ways down a highway, you can buy a "Super Cub" model, which have anywhere from 70-90cc engine. They are "campo" style, more common in rural areas. For getting down town and down the highway, or in the capital or large city, I recommend a Honda or Suzuki 125. That's what the coolest moto-conchos are driving, haha. If you have enough money, you could get a "DT", or an on/off road dirtbike, usually Honda or Suzuki 150s. This is the classiest but also most expensive, but it can get you places the others won't, like through sand or up in the hills.
Words of caution: BE CAREFUL driving here, it's dangerous and motorcycle accidents I believe are the #1 cause of accidental deaths. Bring a good DOT-approved helmet with you, or buy one here, and WEAR IT. You might get laughed at, but who cares. In some places it's the law, and it can save your life. I have seen or known of many people who died just because they didn't have on a helmet.
WATCH YOUR BIKE. They are constant targets of thieves, more so than even cars. Keep the wheel locked, park it where you can see it at all times, write down serial number, etc.
When you buy: Make sure you get a VALID TITLE. Sometimes people try to sell bikes that they don't even have the title for because they never finished paying someone else or the dealer for it, or it's stolen. Only buy one with a valid title, you do not want to deal with that and it can be impounded if you are pulled over and do not have the title. Or worse, there are legal issues and it could get taken from you and you'll never see the money again.
Places to buy used: Well-known pawn shops, or ask around with reliable people if they know someone who is selling. Again, if it doesn't have the actual valid title, don't buy it. Have someone who KNOWS about bikes look it over to make sure it's in good shape and that it hasn't been stripped down and replaced with junk parts. This is common.
ALWAYS take a trusted Dominican with you to buy. Actually, just look around. Then later, send a Dominican or 2 ALONE to look at the bike. You will be amazed at how the price will drop by thousands. When they report back, you can go back with them later. I don't even go by myself to buy a pair of plastic chairs, let alone something that's going to cost that much...
And the Chinese knock-off bikes are junk. You're best off buying new or slightly used if you can afford it.