Where you save in Nicaragua and where you don't, in my experience
One big savings is heating and air-conditioning but this will depend on comfort levels and altitude. I like the weather in Jinotega -- neither heating nor air-conditioning is necessary most of the year, but the reported high has been over 100 F and the reported low, in someone's house, was 47 F.
People who have to have a car will pay more for gas and considerably less for insurance. Prices of used vehicles seem to be roughly in line with the US from what I've been quoted. Insurance is cheaper but in case of need less likely to be painlessly extracted from the insurance company from recent posts here and word of email. Traffic here is more chaotic -- a road to the Jinotega by-pass had a sign "no trucks" after it was recently re-paved and a truck ran right into it. I wouldn't drive here, but then I didn't like being forced into car dependency in the US. People who like cities and the conveniences of true urban life will find most Nicaraguan department capitals quite liveable.
Rent can be considerably cheaper. I rent about half the space I had in Annandale, Virginia, for less than a tenth of what I spent there, but I'm also putting up with a cold water shower. If you need to be isolated from Nicaraguans, the cost of housing can be equal to what retirement in Georgia would be. If you want total climate control, the cost can be interesting from what I've read. If you go the sweaters and fans route, it's cheaper. I'm bringing in more sweaters and winter underwear.
Electronic goods are about a third to two thirds higher. My Acer Aspire was $200 as a refurbished machine with a small battery; Claro sells either the same or a similar model for US $349 plus IVA. I'll see if my local computer store can come up with a USB headset, with a microphone, for $20, which they said they'd have in next week. Rather many people do have computers but they keep them running more years than the US norm. I've been used to turning over machines about every three years or so; I'll be returning to my prior ten year cycle, I suspect, if the machines hold out.
Food varies. Figuring that a quarter to half of car expenses is used for shopping, if you live where you can buy most of what you want in a walking radius, then you're saving rather a lot there before looking at actual food prices. If you eat what most people eat here, the costs are lower than if you need quinoa, tofu, and nut butters. Make your own tofu.
Furniture: the average stuff that you can get delivered is generally more solid wood than its US equivalents at the same or higher price. Getting things made is an option and not that expensive. I don't see good used furniture for sale (or haven't found the store in Jinotega yet). Handmade chairs are something like C$350 from my German furniture maker. A Nicaraguan chest of drawers was C$1,300 more or less if I'm remembering correctly. Cheapo imported computer stand from the American stuff store was around US$30. The Honduran juego de sala was about what a loveseat that needed to be assembled would cost in the US, with one Ikea particle board and steel framed one (assembly required) being cheaper. Avoid Chinese made goods if possible (my sewing machine is a Chinese clone of a treadle singer and doesn't have the fit and finish of that). If you shop around, you can get better furniture than is available in the US for the price, but what I've seen of used furniture is trash. The furniture is assembled and many places (and all the big chains like Gallo Mas Gallo and Distribuadora Luby) deliver about an hour after you get home.
Help: I don't have a maid, so I wouldn't know.
Clothes: I suspect I could find the outlet for factory seconds of my favorite K-Mart jeans as they're made here. The routes to go are looking at the market bins for US clothes being sold quite cheap or having things made or learning to sew. Having things seems to require you to buy the cloth and take it to a seamstress or tailor. Getting shoes made is quite reasonable: C$1,000 for a pair of boots made to measure and in some leather product backed by denim like cloth, which takes about a week. I haven't tried to get things made from actual hides, with glove leather linings. I suspect that would be more.
Pots and pans: bring these from the US unless you know where you can buy good pots and pans. I bought an imported good Teflon frying pan for US$20 in a store here. Haven't seen any All-Clad, so brought my two pots with me. Crockpots show up at the American imports store used and tend to be cheap since Nicaraguans don't tend to use them.
Laundry: oh, get the cylinder of soap and wash things by hand and line dry them. It isn't that big a deal. Otherwise, buy a washer and pay the electric on using it.
Electricity seems cheaper than in most parts of the US. My average bill was something like C$150 to C$180 (my share of the total electric for the house). I suspect if we divided the service and had a meter for each half of the house, we'd fall into the subsidized levels. I hope to do this soon.
Prepaid cell phone -- irk. I have Claro. It's quite a bit higher than Virgin Mobile, but you have to have a cedula and a light or water bill handy, plus bank statements, to get anything else. The more you spend, the longer before it expires. I suspect I pay close to US $30 to $40 on the phone.
I have yet to find fountain pen ink in Nicaragua so brought a bottle back with me which should last for another five to six months (couldn't get more because I only found one bottle). It's around US$10 now for basic Parker Quink in Staples. Mexico seems to be the closest place where Pelikan inks are imported. I don't know of a Staples in Managua, but if there is one, they should be able to get ink. Assume that other exotic (for Nicaragua) interests will be about twice as expensive as in the bigger US cities.
Horses appear to be cheaper at the lower end of riding stock; equally pricey if you're interested in show horses. I haven't seen any heavy draft horses in Nicaragua; that's ox work.