where can I find estimated costs of laboratory equipment?
The best way (if you're buying new) is to contact the manufacturer/distributor. Sales people get inquiries like this all the time, and are generally more than happy to accommodate you (because they get commission on any sales they make). Most items have customized pricing depending on the customer, their order history, the number of items being ordered, add-ons like maintenance contracts, reagents, etc. Many complex instruments like flow cytometers have many customization options, including the number and type of lasers, different types of filter sets, tube vs. plate-based acquisition, type of computer, licenses for software, etc. Sales people know their company's product lines the best, and are willing to talk to you to figure out your needs and then recommend the product that works best for you, which may not necessarily be the one you were originally thinking of.

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