Online Supermarket - Part 4

Raghav, thanks for the posts.. It did throw some light on some of the questions I was pondering on..
Some points which I wanted to add just to extend my idea.. and a few questions which should be answered before we can even think of the feasibility of this stuff...
Website:
For sure there are enough web technologies in the world to get a nice user friendly site up.. which doesnt make you go multiple pages to even select one item.. I saw the site you mentioned.. I felt it was not very user friendly.. They used ASP.NET pages but nothing else...
We can make the website incorporating AJAX.. which is supported in .NET 3.5 framework.. I have been using AJAX at workplace for some of the online tools we have developed for our customer... Infact one of the applications is only a single page with multiple tabs and everything.. every query you make is an AJAX call.. and the user never sees a page reload..
We could remember a customer's previous month's order.. or let him set up a custom order.. and store it in a SQL database or something.. and we should assure them of security...
Logistics:
Since we cannot have transport at once to cover a complete city I believe it has to start off with some areas where it will click off the most.. the most affluent areas or areas with busy people.. like IT employees concentration... etc.. The main problem is how to deal with home deliveries... what sort of transportation facilities will be needed for delivery personnel to carry on with their work... and how to facilitate taking orders etc... this is one major concern as far as this idea goes.. and tops the list of expenditures.. and how many people to start off with?
Support:
Do we need support? Issues desk to resolve any issues reported by customers? Do we need it immediately or can put it on hold?
Advertisements:
How will people come to know of such a portal? What should be the advertisement strategy? Something as simple a pamphlets will do?
Tie-ups:
With what sort of retailers would you like tie-ups... Once this idea gets into their minds.. our portal is out of question.. they definitely have enough potential and resources to make a better one.. so competition.. but can we afford to buy all rations by ourselves before we can start off with the portal.. will people buy? And can we give them an advantage of choosing from multiple retailers...? Like buy Boost from Reliance, Coffee from Heritage and Surf from Food Bazaar.. (they may do this as the respective retailers might be providing these at lowest prices).. What sort of agreement if any should be maintained with the retailers..
Online Payment:
This is one thing which obviously is an issue.. tie up with a bank or anything like that is bound to take time.. and with so many banks around it much more tougher and can we rely on our personnel completely for taking payments from customers? Is it a safe bet.. One solution is tie up with an already existing portal like Paynet, which supports online payment from many banks..
Min number of items:
And yes we would definitely need to set a min amount for which door delivery will be provided.. obviously a customer cannot ask for a single matchbox on our website and we start delivering it..

These are some points I was pondering upon.. well guys let me know what are your views....