I'm a contractor ... BOO! My wife hates it when I do that. It looses it's affect on the internet, though.
There are basic costs to every addition. The bones of the job, foundation, framing, roofing,and siding are the least cost. It's the finish details that can drive up costs.Some costs are locally mandated. Blueprints(i.e.Architects)alone can cost a few thousand, or a few hundred. The more detailed your plan is, the better.
First thing to do is find out what requirements San Antonio has in the way of building permits and plan requirements. Here in East Williston ,NY if you put on an addition there are about 10 inspections you need to go through. Everything from escavation of the hole in the ground to insulation inspections. There would be electrical permits, plumbing permits and construction permits. There are fees for all of these.
You need to spend some time researching this. Once you have a set plan ,start calling contractors. Start with the ones that have worked for friends ,neighbors or relatives. Look at the jobs with a critical eye. Many people will give glowing reports about mediocre work.
Ron

My solution was to do all the work myself, including the design, pulling the permits, and all the work (except the gutters because those are seamless). All that may or may not be possible for you, e.g., the local building department may not allow you to do all the work, but the further along that spectrum you can get, the more you can save. You can read about my experiences on my blog.

99% of my training for it came from volunteering with Habitat for Humanity. There's an affiliate in San Antonio, and regardless of how much work you do yourself, I'd highly recommend volunteering. It's a fun experience, it's a great cause, and a great and free way to learn about how houses are built. Even if you hired a contractor for everything, you'd have a better understanding of the work they're doing, and better knowledge of what's possible.

Here is a link that might be useful: DIY Insanity

Some other things you can consider in the design:

- Stick to as square/rectangular a layout as you can stand. Bumpouts, additional corners, etc., all add extra labor, which you pay for.
- Stick to standard sizes and patterns. You mentioned using standard window sizes, which is good. Also think about the plans in terms of even multiples --if you can go 15 or 16 feet, 16 feet likely will require less measuring and cutting. Think about using stock cabinetry instead of custom; stock fronts instead of special orders; ordinary casings and moldings instead of special stuff.
- Don't make changes once the plans are done unless you're fixing errors. Every change is $$$. Think it all through before you proceed. Be as specific as you can about things like window quality (even brand and model), siding, door styles and construction, what doorknobs are to be used, etc. Any ambiguity is an invitation to a surprise. Neither you nor the contractor can read each others' minds.
- Negotiate with the contractor on who supplies pieces-parts like electrical outlets, overhead lamps, etc. If you plan to do that yourself to save money, make sure that is part of the contract and that you will be notified when those items need to be on-site.
- Don't be afraid to ask for a better price. Keep in mind that negotiation is a two-way street. Maybe you can get a few hundred dollars off if you let the contractor put an advertising sign on your lawn for the duration of the job. Maybe you can get a better rate by waiting for a slower work period or for being flexible on how long the job will take. Ask about "paint-your-way-in" or if there is some demo or prep work you can do. Maybe you get the dumping bin and the permits, paying for them directly. Asking is free. The worst anyone can do is to say 'no'.
- Keep in mind that you are doing 'wet' remodeling. If you were not putting in a laundry room, you probably wouldn't be talking about water and gas (or 240V electric) connections. Putting those in will require labor and additional subcontractors. Think seriously about whether that's the best place to move the laundry room. OTOH, it may be cheaper to route new connections into the addition than to reroute into existing parts of the house. But talk it over with a plumber and electrician or two (offer to pay for the estimate since the contractor likely has his/her own subs) before insisting in the contract that you want it in the addition.
- Finally, think about what you/DH can do later and what you need to have tradespeople do now. Maybe it's cheaper to go with builder-grade carpet on concrete for now, because you can put in a floor of your choice later. Spend the money on things which will be difficult/more expensive to retrofit or which will cost you to go without, like gutters or sufficient electrical connections.
Good luck!

Thanks to one and all for the great suggestions. I may have exaggerated a bit with the "terrified" word but it's a scary thing, planning to spend a ton of money on something that I know basically nothing about! I have carefully worked out a design for a laundry room placing it directly on the wall behind the kitchen sink, hoping that the plumbing for the W/D can go there, eliminating the need to move or install all new plumbing. I am hungry for any advice, opinions or other info anyone can provide and I so appreciate the advice given so far!

Mary

Hi Mary:
Really great advice so far. I just finished a a 550 square foot second story addition and wanted to emphasize how important it is to find a contractor you like and with whom you work really well. This aspect helps a lot when unforseen changes come along. After construction began, my architect (who actually worked many times with my contractor) said that another large beam was necessary to support the second story (in addition to the specified two in the plans). My contractor just charged me for materials and a really nominal feel to construct them. He and I had a great rapport. I made lunch for he and his boys every Friday and in turn, he would really try hard to keep fees down. When I changed the design of the plan and had him tile an alcove for the vanity, he charged no change order fee and a nominal labor fee. I can count numerous instances demonstrating how a good relationship with him saved thousands of dollars in extra fees which any other contractor would have charged in change orders.

I also have had really good luck by purposely picking small, highly rated contractors on Angie's List. I sort by any contractor rated B or higher and then try to pick contractors with smaller operations. The bigger operations have office staff and marketing cost, which quite frankly, you are paying for in his fees somewhere. I saved $20+/sq foot on granite installation this way with one contractor, and the contractor for my addition was 30-40% lower because he was a one-man operation who employed a couple master carpenters when necessary. His overhead was very low.

Finally, you can really save a boatload of money buying your own materials, but it takes ALOT of time. I spent oodles of time on the internet researching prices. I also called around to stores. In Cincy, there is a closeout warehouse that goes to auctions to buy returns from big-box stores. My $2000 Andersen arch window was $250, but I had to look through stacks of windows and take a magnifying glass to each one and look for printing that said "tempered glass" (requirement over a bathroom window). It probably took 2-3 hours, I had to pay cash and get it home myself.

Anyway, good luck with the remodel. It's fun, but stressful.

Kim

I also have had really good luck by purposely picking small, highly rated contractors on Angie's List.

Excellent point. For several years, I have subscribed to Angie's List. I am finding that, on AL, success begets success, sometimes unsustainably so. In a few categories, there are a few ubercontractors with great ratings who seem to get the bulk of the business because they are hired by customers who see the great ratings. That's not to knock these tradespeople or the List, but there are plenty of contractors listed in a category who maybe don't have oodles of feedback, but what feedback there is, is good.

I've hired some of these folks and found it's much easier to get them on my schedule and more willing to take on smaller jobs. I have found them very competent and easy to work with. I don't know as they're necessarily cheaper than the "stars" but they certainly are competitively priced. Sometimes they're cheaper because they're just starting out or they are smaller outfits. Whatever, they have the flexibility and skill to do what I need to have done -- and the big guys started small, too.

The contractor we ultimately hired suggested that we have them take the project up through drywall and that we hire the finish work individually. They said as remodelers, they don't get volume discounts like builders do, so having them take care of the finish work wouldn't represent any savings. We took them up on that recommendation and actually ended up doing ALL of the finish work ourselves. That saved a bundle of money.

Hi Mary,
Painting is another area where you could shave off some LABOR costs. Notice I said "labor".
* You can usually save a few $hundred this way, and upgrade the actual quality of primers/paints chosen by painting yourself.
* Typically (unless specified!!), builders/remodelers just factor in the lowest price primers/paints, but charge full retail on top of labor.
* Use top-notch rollers/brushes however, AND DON'T SKIP PRIMING!
* Then, 2 topcoats of paint.
* I WOULD hire someone to spray "orange-peel" texture on the drywall though...IF you're not going with smooth walls.
* Prime after texture has dried a day or more.
* Most top-line paints range from $20-$45/gal.
* GOOD primers are $15-$25/gal.
* Figure out your actual paintable wall-area.
* Most paints/primers do ~ 400sf/gal. So...a 12'x14' room would need 1 gal. of primer & 2 gal's of paint (for 2 coats). 52' around perimeter x 8' walls = 416sf...minus the approx. door/window sf, comes to ~ 400sf.

Happy cost-cutting!
Faron