Its too bad OP couldn't just stay on the remodeling forum - why did he feel compelled to come here? This forum was set up specifically for the preservationist/restorationist (vs remodeler) so we wouldn't have to be bogged down with this and the vinyl siding issue every other post. Ughhhhh enough already. It's a lot like debating politics and religion. There are beliefs you are either on board with - or you're not. Re: old house windows, the beliefs we preservationists/restorationists operate from are a) there are very little energy savings with new windows (ie most heat loss is via gaps, air leaks, lack of insulation in basemen and attic and very little through the panes of glass/windows themselves); and b) when you add up costs of manufacture and shipping, short operating life, inability to repair them, etc. the "green" alternative really is repair/restoration of old double hung wood windows and c) cost - huge expense, short operating life & inability to repair adds up to not a very wise purchase Unless original windows are missing or too hopelessly trashed - some original windows from 1940s onward weren't great quality to begin with.

We paid about $1000/window in the SF Bay Area for wooden double-paned double-hung windows designed to match the originals, which was on the low end of the custom bids we got and on the high end of the out-of-the-box wooden windows we looked at. (We went custom because the rest of the windows are still original, so we didn't want the two we replaced to look out of place.) You can get simple wooden double-hungs for $500ish in NorCal if the city doesn't care that they be "authentic" (which they may not---in our city, you just aren't allowed to put the vinyl or aluminum sliders in old houses, but as long as it's generally in keeping with the look they don't care beyond that). I'd give the city a call to find out for sure, though.

Removing Paint from Siding. There are two tools that, in our experience, are very good at taking paint off siding, and a lot better than the traditional heat and scrape, or scrape and sand methods.. 1. Silent Paint Remover is one. This tool is a GIANT STEP above heat guns and the dangers they cause. The other is 2. Paint Shaver. This is a mechanical, high speed stripper that uses replaceable carbide blades. Which one we use depends on the paint to be removed. Silent Paint Remover is slower, but does a very neat job requiring very little sanding. Paint Shaver is faster, but takes a bit of practice to remove the paint without putting a lot of crescent-shaped divots in your siding that require a lot of sanding out. One mistake to guard against using this tool is setting the depth adjustment for too-aggressive a cut. You don't need to remove all the paint, just the loose paint, so don't try to get down to bare wood in one pass. When you are removing paint, you hope the original painter did a lousy job so it will come off easily. If he was good at his job, it's going to come off hard no matter what tool you use. Keep in mind that the EPA lead abatement rules govern the safe removal of any exterior lead paint. As a homeowner, they may not apply to you, but follow them anyway for everyone's safety. Both of these tools are commonly available at a deep discount over retail from e-Bay and Graig's list. We have used and cannot recommend the Metabo or Wagner machines. They don't work nearly as well as the suggested machines. Repairing Plaster To repair cracked or falling-off true plaster you need to reattach it to the wood or metal lath underneath. The traditional way is with screws and plaster washers. These usually extend proud of the wall, making them difficult to conceal except with thick coats of patching plaster. The better way is to glue the plaster to the lath. There is a commercial kit to do this called Plaster Magic which we like, but which we also think is pretty expensive. We just use our own, locally available materials, that work just as well and are a lot less expensive. Here's what to do: 1. Using a concrete bit, drill about 3/8" holes in the plaster until you hit the lath -- do not drill through the lath. You will feel it when you reach the lath. You will want to drill about 1" on both sides of any crack, putting a hole about every 4-6" along the crack. Its a judgment call. Drill as many holes as you think you will need. If in doubt, more is usually better. For large loose areas, drill about every 4"-6" in the field and every 4" around the perimeter of the loose plaster area. Sometimes you will hit the gaps between lath strips. Don't worry about it. Just move about 1" away and drill again. 2. With your trusty shop vac, suck the plaster dust out of each hole. This is important, plaster dust interferes with the adhesive. 3. Using your caulk gun and a good construction adhesive (we like Power Grab, but any quality adhesive should work. In a pinch, we have used most of them at one time or another and none have failed.) squirt a good glob of adhesive into each hole. This will probably be messy, so have some mineral spirits and rags around to cleanup any drip-out. 4. Make a bunch of 4" square wood washers. You can make them out of job scrap. We use 1/2" or 3/4" OSB most of the time just because it happens to be around. Drill a hole in the center of each washer - 3/16" or 1/4" ought to do it. 5. Line the washers up with the holes you drilled earlier and, using a drywall screw, attach the washer to the wood lath beneath the plaster. You don't need to screw into every hole, about every 4-6 holes is a good rule of thumb. What you want to do is put even pressure over the loose plaster area and draw it back to the lath. This will allow the adhesive you just applied to bond the lath tightly to the plaster once again. As you tighten the screw, you will feel the plaster draw in. DO NOT try to sink the screws all the way in one go. Draw them in gradually moving from screw to screw. This lessens the risk of cracking the plaster further. When all the screws are sunk, you are done until tomorrow. Go have a beer. 6. After 24 hours, remove the screws, put them back in the box (they can be reused) and throw the washers away. The plaster is now stuck solidly to the lath once again. There are no screws or washers in the wall - so finishing the plaster is much simplified, and this fix is strong. The adhesive sticks like, well, like glue. 7. Using patching plaster, a setting joint compound, or even regular joint compound, patch the screw holes, cracks and fill in any missing plaster. The purists will tell you that joint compound has a different texture than real plaster and is softer, so you should not use it. It does have a different texture and is softer, but so what? The paint will hide any differences. 8. We recommend against paper tape on cracks. What we use is nylon screening -- the stuff in screen doors. buy a role from your hardware store and cut it into 6" strips while it is still rolled up -- its easy to cut with normal shop shears or even your utility knife. Use this in place of nylon mesh tape -- it works better. We embed it in a thin coat of joint compound, then, when the first coat of mud has set, mud over it. Its wider footprint is better at stabilizing cracks than narrow nylon mesh tape. In fact, we have never had a repair fail using this method. Removing Layers of Paint from Interior Trim Definitely use a commercial stripping service if you have one in your area. At $1.00 - $2.00 per linear foot, the price is well worth not having to deal with the mess of stripping in place or on saw horses in your garage. After stripping be sure to sand with a fine sandpaper to remove the fuzzing that stripping causes. Good luck.

+1. I would look at storm windows with LoE glass and additional insulation around the windows. The cost of lead paint containment alone is going to be around $100 per window so that only leaves you $250-$300 including labor. It can be done but you would be putting a very cheap quality window in that is likely worse than what you have now. If your home has poor attic and wall insulation, I would look more towards improving on that than I would about windows. Have you had an energy audit done? If not, that's where I would start.