Per my discussion with Dante, and because my experiences do not in my opinion warrant a separately searchable data sheet, I'm appending mine to his. Even if it is, we'll come up in the same search (Edit: I ended up writing more than I thought I would, as usual).
I flew into Santo Domingo on December 29th. After you get off the plane, you'll have to walk through immigration, and hand in both of the forms they gave you on the plane, as well as pay an entry fee (10$) and fill out an additional form when you pay the fee. That desk is just before the immigration line (which didn't have anyone on it), so bounce over to the right, fill out the paperwork, pay your entry fee, and then go to the immigration queue. It seems to be a rubber stamp process and I was through in a moment. However there was a dog sniffing luggage inside by customs clearance, so perhaps don't pack your own supplies, you blazers.
The Santo Domingo airport is actually in Boca Chica, so if you're considering hitting both, you might consider going to BC at the end or beginning of your choice. Pretty much universally, i was quoted $40 dollars to and from the airport to Malecon. Going back I checked around a bunch and got the same reply (1700 pesos). To find the cab away from the airport, look for the uniformed guy nearest door out of the building, follow him to the left to the dispatcher and there you go. The ride to Malecon (the Port or Jetty), where I stayed, was 25 minutes or so, depending on traffic.
Like Dantes and many others, I booked into the Napoletano. The good about it is that they bothered me not at all about my guest, a young women who spent three of my four nights with me in the hotel. It was never mentioned. The waiter at the poolside restaurant, La Terrassa, where they serve the included buffet breakfast did ask the one time we went together if she wanted the buffet - I said yes but she said no, but had she eaten, we would have paid. I don't know what would have happened if I booked the room for two. All in, I believe I paid around $425 for the room for four nights. Before taxes it was 330, but taxes are like 28% in the DR, and so the overall cost was significantly higher. Keep that in mind vs. AirBnB possibilities (which I looked at but ultimately decided against). I did book it through Pointshound (same price as on expedia) and got 1600 Alaska airlines points for the booking as well.
I thought the room was fairly mediocre given the price, actually. Oldish mattress, shitty toiletries (maybe bring your own if you care) and mediocre water pressure. Water seemed to hard to get a lather on the soap. Bad bedding as well.
On the other hand, the staff was largely very pleasant (and often cute), and the pool deck on the second floor, despite lacking many comfortable lounge chairs, is fairly ideal for a date than can easily escalate. E.g....
I invited my girl to the pool. Told her to bring her swimsuit,after meeting, we went up to the room, she changed, we went back to the pool, swam, had some lunch, back to the room in the late PM, and closed.
Location-wise, the pool deck-restaurant overlooks the ocean, which is quite pleasant. The food is fairly mediocre and not inexpensive by DR standards. All that said, I didn't find the DR to be very cheap as compared to places I've been in Asia or other third world countries. I'm sure its much cheaper outside Santo Domingo, but in SD, taxis weren't a bargain, even after negotiation. Menu prices on the two restaurants I frequented most (La Terrassa, at the Napolitano pool, and Luis Parillades, which is on the waterfront three blocks away from the hotel going towards Zona Colonial, a very pleasant spot with nice views) weren't cheap. Without drinking, expect to spend around $25 minimum for a dinner date at either of those two spots. I did like the food at Luis Parillades, though - apparently its a fairly well known spot and has been featured in commercials for its scenic appearance.
Heading down El Malecon waterfront in the other direction towards Ciudad Nuevo, you'll pass a few pizzerias on the right, and a jetty on the left that has some fast food takeaway spots. They had concerts and an outdoor fair going on during my stay, which was over New Years. Lots of families and people milling about. Many people come to Malecon just to hang out and walk the waterfront. There is broken glass everywhere - wear enclosed shoes or tread carefully.
I spent my first night in a bodega drinking beer basically on the street. The weather was quite pleasant that night and it was fine, as I practiced my spanish with a local dude who was there. The bodegas and liquor stores where they serve drinks dominate nightlife in that part of Santo Domingo, as Dominicans don't seem too reliant on fancy ambience to get their drink on. In fact, though I don't know who he was, a professional baseball player was drinking in the same bodega - clearly he could afford more but that's where he chose to hang.
I'll be clear that I wasn't hassled at all on Malecon, not even by hawkers, except the taxi drivers outside the hotel. In Zona Colonia, which is the red light district and which I only visited once around lunchtime, the hawkers did approach me, as did street beggars. I was wearing headphones, though, and just keep walking, and nothing was aggressive in the least. I didn't venture far and wide, but felt zero threat during my whole trip. I walked through El Conde end to end, and it frankly wasn't particularly interesting. I stopped for a blended fruit drink, sat for a few moments, and had the luck to spot this guy and his wonderful footwear. He might be punching over his weight to pull any "woman."
Further west along Malecon there is a Crowne Plaza and then a Sheraton. While I was there, I checked the rates online and both were listed at 109/night. Presumably the rate would be increased by the taxes as well, and thus be a good 30-40 percent higher than Napoletano. Those hotels did look much nicer to be sure, with the Sheraton definitely looking like a step up from the Crowne. No idea of their door policies. The restaurant in the sheraton was quite reasonable in price (not really more expensive than the others mentioned) and I'd recommend it (especially the fresh grilled fish).
I met up with Conquistador at Agora mall, which I spent a few hours in. It was NYE so I don't know that the crowd was particularly typical of the place, and there were some decent looking girls walking around, mostly with other girls or with boyfriends/husbands. The mall doesn't really have available wifi (or at least I couldn't get connected for data service). In fact I couldn't even get data roaming around the mall on a new iPhone 6+ (Verizon) on the Claro network). It may be that the mall overwhelms the capacity of the local servers to provide data service). Conquistador spent the evening with me and my date for NYE, at la Terrasa where they had a party. Eventually he headed off to a huge free concert down the shore in Malecon. He's a solid fellow and knowledgeable about latin america. I wish him luck.
Departing was fairly straight-forward. American Express platinum holders can use the Amex Lounge in Terminal B, even if flying out of terminal A. There is also a Star Alliance lounge that works with Priority Pass but not for the Priority Pass card provided for AMEX platinums. The lounges are next to each other.
Overall I had a nice time, but that was largely the result of meeting the girl, who was very pleasant, polite, ladylike and thin, and who had an ass like a fresh peach. If I was bouncing girl to girl, I likely wouldn't have had as much fun, though one never knows. I pipelined more girls than I could have had time to reasonably meet, and then didn't end up meeting any of the pipelinees (the girl I spent time messaged me on LatinAmerican Cupid the first morning after I arrived and we made an immediate date).
Whatsapp is still the dominant form of communication for girls in SD. I had the Cupid account, I spoofed gps on Tinder with Tools for Tinder, and added a tagged account. Tagged quality to me was pretty low. Lat Am cupid was variable, and tinder was glitchy (less so when I was actually in SD) but the quality was decent. I am still getting messaged by tinder matches and girls I moved over to Whatsapp. All of the girls with whom I ultimately connected were between 19-24, and I used my real age of 44, for whatever that's worth.
Girl-wise, in SD things tilt more towards darker skin girls and girls with a bit of a belly/ass. You can find outliers like I did. My girl is from San Francisco, Dominican Republic, closer to Santiago. This was consistent between day game and online, though maybe more prominent in online.
My limited Spanish played fine for the most part and I got around fine. It improved over even just the four days I spent there. I haven't studied or use Spanish regularly in perhaps 25 years, so it was nice to see I still have some aptitude. I did download and use Duolingo for a few weeks before visiting, which was decent as a vocabulary refresher.
Overall impressions of SD are that it was worth it for a visit but the arb on costs isn't high enough given its lack of infrastructure and quality of girls to be really enticing as a location for players who are location independent and looking to relocate. However, if you prefer Morenas with a little more meat than I do, you might think differently.
Dantes, you should indicate more about your logistics and process for getting to Santiago and then to Sosua/Cabarete. That would be useful.