We've all been there - the sales person says "Hey everyone, I've just got us a new project!". At this point all the engineers look at each other, and realise that none of them have been spoken to regarding the project.
As one, they exclaim the hallowed word, echoed throughout time - "Dammit*.".
* Note: actual language used may be... stronger, let's say
They know what's about to happen - they're about to be asked to deliver a project that has been scoped out by the sales team, and will inevitably have bizarre requirements, unachievable deadlines, or both! "Why oh why did no one ask us about this? We would've helped!".
Sales teams are incredible. Their ability to take client problems and figure out how their specific company's tech can help them solve it is nothing short of miraculous. The documents and proposal they create are worthy of literacy awards, and the RoI promised is nothing short of Bill-Gates-money amazing.
The problem is that unless they've spoken to someone in the engineering team, any dates or cost for that integration are almost certainly wrong, along with assumptions about what the underlying technologies may be, and how they fit together.
Just because you don't have any specific sales engineers (or whatever you want to call them), this doesn't mean your current engineers cannot help with the sales process. If you don't feel that they'd be good in front of clients, then fine - just take down the client requirements in as much detail as you can, and then take that to them. We engineers love figuring out how we can solve a problem, and we'll be delighted you included us in the process. You can then take your discoveries back to the client, and have a more informed conversation about what you can offer.
If you are lucky enough to have dedicated sales engineers, then amazing; get them involved as soon as you can! Put them in front of a client, and let that conversation begin.
Even if you're in the incredibly rare boat of having fully-fledged engineers within your sales team, then I still urge you to get the delivery team engineers involved. Their being on the frontline of developing solutions will always give them more context than those who are not.
The point is, engineers provide valuable insight into accurately estimating and understanding a project. There will be nuances no one has thought of, intricacies that escape both parties, and similarities (including problems faced) to previous solutions that are only obvious to them.
If this is your mindset, that needs to change right now. If your engineers are simply code-monkeys who do what they're told, you're losing out on so much value. Give them the chance to input into the solution, and I guarantee the end result will be better for it.
I'm lucky enough to work at DVELP, where we take our engineers seriously, and our engineering-first mindset is a core tenant of our value to clients. We get engineers involved as early as possible, start talking shop, and make wonderful things happen. As a happy coincidence, clients love seeing that we get engineers involved early and often - it shows dedication and commitment that we're taking their problem seriously.
So yeah - trust your engineers, and get them involved. You'll love what happens.