You are going to want to do a quick bit of research on elastomeric paint and application techniques. I searched elastomeric paint and a bunch of information popped up. It's a good idea to educate yourself before you take on the painter. Just about every paint and coating company will sell a version of the product. They are all tintable. It can be sprayed on with a monster sprayer and the right tip. But, it will have to be back rolled. My guys rolled it. I'm glad it's such a fixable problem. You will be pissed when you see the bill. I think the best you can expect is a no profit job and materials at cost. At least this won't stop the CO process.

If they are "suddenly responsive" - I'd get some sort of structural inspector and talk to your neighbors. I'd hate to have this go bad later and the builder comes back with "hey - we even went back WELL AFTER the 1 year warranty period to dowry and this was not mentioned". It seems fishy that they suddenly give a darn about customer satisfaction. Invest in a report by a professional. If your neighbors are seeing the same - go in together on a group buy. Focus on homes started the same time as yours - as my experience has been that cheater and quality issues seem to degrade over time - i.e. superintendent starts out doing everything right and little by little...... with less and less supervision...... And you might want to find your permit and see if you and see all the inspection notes your county's website - see if your house failed anything like footings, etc.

I'm kinda surprised your lender didn't have an inspector or require one. I'm in a new house, also in a thaw-freeze area, but just over a year ahead of you (year warranty extended because of COVID to minimize people in the house). I have the same problem determining what's important, and it makes me anxious: I don't want anything to get past me, but I also don't want to go into worry-wart mode over something non essential. Apart from technical flaws, there's a separate issue of what is just plain unacceptable. Sloppiness is in this category. I would not caulk or cover or conceal anything until AFTER the one year so you have satisfaction from the builder. Freeze/thaw causes settling, and that can create some alarming-looking cracks. We are just finishing winter, and they may grow or shrink. At any rate, they don't always look the same from one week to the next. Mine aren't too much to irritate me, I do know my builder often has to fill minor cracking during the warranty year. It's normal. While concrete cracking is also normal around here, there are different degrees of it. If your home is on a concrete slab, I'd have an inspector check it. It would definitely be a warranty issue if there's a problem underneath the house. AFAIK there are better or worse conditions to make concrete in, and either some short cuts might have been taken or COVID messed up the build schedule or..... Get it checked. I'd insist they fix the stair "cosmetics" to my satisfaction: those are in the area of completely unacceptable to me, and they're a potential tripping hazard (imagine your toe hitting the edge). There's something definitely wrong with the balcony jury-rig. The "vertical" lines don't all seem to be vertical. For freeze/thaw reasons, builders do use wood shims in this area (though I have no idea if they'd use them in that particular spot), but those shims just look half-baked. ******** While we're doing spring—and we have thaws and rains—there may be some more things to check that may have nothing to do with the build, but are smart to do. I'm sure other folks here can offer some more. A few: -check the dripline from the roof. Make sure water is flowing away from the house. Is there a one-foot margin (pebble, rock, gravel?) around the house to minimize splash? -check all the windows to make sure air didn't leak between the panes -have a good look at the siding. Is it buckling, slipping, etc.? -check water-bearing fixtures (e.g. sinks, toilets, W/D) for any sign of water leakage. -sketch a map of your lot, the house, the trees, everything you see....Take a lot of photos. Then, next winter you'll be in a place to plan landscaping etc. with every season accounted for. Houzzers recommended I wait a year before I made major landscaping decisions, so I could get used to the property. They were so right!

Everything you posted points to unstable foundation that has probably been going on for years. You can hire engineers and try overcoming it but after 27 years I suspect remedies have been tried and failed. Another option is hiring a paint contractor to "doctor it" like the people that sold it to you did then sell it to another unsuspecting buyer.