Sorry to hear of this problem, and you are asking the right questions. kimmsr is right... and "ingestion" also includes passive ingestion of soil from hands or dust that gets into your mouth from the air. Children have a much higher passive ingestion rate, hence lower safe values for soil where children are present. If you are doing phytoremediation with sunflowers or anything else, the plants should be landfilled, not composted or reused in any way. That's if you actually plant something in the high lead soil that you know will take up lead. A lot of this stuff got where it is prior to regulations preventing it, so unless it was illegal burning and disposal post-1980 or so (RCRA), and if the seller didn't know about it, it is most likely not actionable by env. agencies. YMMV in your state. So, you gave us the lead numbers, and those are marginal for residential - my state uses 260, EPA uses 400, and you say you have "400 to 600 in the good area". What about the average across the yard, how many samples did you take, were they from 0-1 ft. or from 1 ft. discretely, and how high is it in the 'bad' areas? And what about the arsenic levels? Did you have that tested?

@Laura Hoefer seems like your situation is not as bad as ours in terms of exposure. We didn't know about the windows and my kid's bed was right by them. He got exposed a lot with all the opening and closing. Plus the age doesn't help - he still puts everything in his mouth. If you decide to strip them yourself, I would advise to take a class on lead safety. That being said seems like it's a very complicated process and it might make the situation worse. There are some sealing paints for lead, but you'll still have to scrape the peeling paint off, which is dangerous. I'm going to strip only the 1st floor windows as it gets warmer (they are 8 ft tall so super expensive to replace), but we decided to replace the rest. Restoring is even more expensive if a professional is hired. Have you tried using professional lead cleaning products for lead to mop the floors? Maybe this will help reduce the exposure for your kids. It's all so scary. I'm scared that my kid will be permanently brain-damaged due to all of this :(

Your choice of remover is fine, but cover it so that you’re “working wet.” I’d still wear gloves and a mask (better safe than sorry), but if the paint and remover are gooey when you scrape, dust exposure won’t be an issue. Clean with rags and water (not a vacuum or a broom). Dispose of cleanup materials as specified in your area (hazardous). In an older house, unless you test, I think it’s best to assume lead, asbestos, etc.

I have a 1920 house. I can tell you the wishes to add will add up to over 100 if you do it with permits and hire out. Here is the breakdown of our costs over the 15 years we owned our house. Finished the basement ourselves, materials alone were 10k New appliances,sink, lighting bacsplash, added outlets to code and kitchen counters only no gutting or layout changes 16k. 15 years later we are getting quotes on a true remodel these are between 50k and 110k dependant on layout and brands. Adding a master bath above an existing first floor sunroom above 50k New driveway and landscape because upgrading plumbing for bath meant tearing through the drive way 12k Upgraded electric 8k New high effeciancy boiler 10k Adding ac 22k Our new quotes to do the roof are 8k but we only have a single roof layer if there are multiple layers the price is substantially higher. It looks like you need new siding I do not know the cost for that but we paid 4k to tie our new addition siding into our existing. It was an 8×13 foot structure. We will recoup our investments if we were to sell because we have owned long enough to do so and it sounds like you are acquiring this to keep in the family so it may very well be worth doing. However, I find shows showing how to turn a fixer upper into a showcase on budgets smaller than 120k very misleading and dangerous. It would have been much cheaper and quicker to have listed rather than to love it but my location and neighbors are too important to us and the older character is special. But these came at a large cost. Good luck with your restorations.