Those high quotes you're seeing aren't just seasonal spikes, they reflect the current reality of specialized trades right now. When you're talking about structural beam reinforcement and heavy plates, you aren't getting general fabrication rates; you're getting rates for structural welding, which carries much higher insurance and liability costs for the shop. Most quotes are higher than you'd expect because they're factoring in the time needed to prep the material correctly and get certified inspectors to check the finished welds. If you want to scope this out better, you need to stop just asking for a total price. When you call up a shop, demand a separate breakdown. I want to see exactly how much they charge for the steel itself versus their labor rate and consumables. Then, specify the work down to the inch. Don't just say 'reinforce the beam'. Tell them exactly what is being joined, what the plate thickness is, and what code you need the welds to meet. This forces them to give you a more accurate estimate instead of just giving you a high lump sum. As for the general market, while there are labor shortages for specific, high-skill positions, it's not always a permanent change. But the prices we are seeing are certainly reflective of the current difficulty in finding tradespeople who have the specific certification and experience needed for structural work. Waiting around usually ends with the price increasing, so it's better to get three itemized bids early rather than hoping the market corrects itself.
Remember that quality and safety are crucial here. Structural failure isn't an option. A cheaper, rushed job now will be a massive problem later, so treating the shop like a professional contractor and demanding detailed documentation is the best way to avoid getting ripped off.