Oh dear...
...another over complicated project bites the dust.
The only sad thing is they won't learn - Do the simplest thing that works first. You won't realise all your savings but you'll have something that works that can be subject to improvement in small increments.
PHB: and we get a .000001% error rate typing in zip codes
Salesman: We can eliminate that with GPS and know within 2meters where someone lives.
PHB: Oh yes we'll have some of that. I can do population density by square meters instead of state/county/town/parish. I can generate some very pretty charts from that. (forgetting that the information is out of date the day after it is collected)
Techie: (thinks) Yep Geospatial coding - that'll look good on the CV.
PM: Impact analysis, revised plan, change control blah blah blah lots of days, team just doubled.
Bean counter: Kerrrrching. Cost just doubled on the simple PDA that had two forms: address details and occupancy details.
PHB: You didn't say it was going to cost more, I think we'll drop the whole project.
or worse
PHB: Ok we understand we can't afford it and we don't have time to implement properly it but there's no need to be pessimistic I'm sure there will be some new technology during the course of the project that we can bring in to shortcut it. And we need a project code for hand held terminals that allow five finger typing...hmmm Terminal 5 ok with everone?
Nobody looked good because it wouldn't look good to say no.
Having seen these things go tits-up before as a lead architect I thing it's my job start with a negotiating position of "no" and work up from there. Not always popular with anyone, until you deliver on time and to budget and then get an order for refinements and the time to do them properly.
Flames for all the public sector projects that will crash and burn because the blue sky thinking and sales technique is way ahead of technical and people capabilities.