We are an engineering services firm that is in beta testing on software. To date we have self funded, but we are thinking about seeking investment to get us to the next level, as well as an experienced investor who can help us avoid landmines.
Since you mentioned you're raising a seed round, I strongly suggest not using an investment banker. At the seed stage, VCs are investing in you more than your business—putting a banker in the middle will do you a lot of disservice. IBs are typically used for Series B and beyond.
I also noticed that you call yourself an engineering services firm—typically services companies don't make good VC fundable businesses. If you have a product that you can spin off and raise money for, that might be more attractive. Happy to chat in more detail about the fundraising process if you wish.