I don't think you want a vacuuming robot. Those already exist, its called a Roomba, and they have a lot of limitations that are completely intractible in their given form factor. You have to modify how you use your house to make it actually useful enough. Some examples:
1. Stairs. Roomba's can't vacuum stairs, so you still need to do those yourself.
2. Stairs, Roomba's can't traverse stairs, so you need one for each floor.
3. Doors. If you want the Roomba to vacuum the whole house, you have to have all the doors open for it.
4. Can't have anything on the floor, the Roomba will either get stuck or avoid it. But I shouldn't have to never leave a backpack on my floor if I want it vacuumed.
5. Corners. Roomba's can't vacuum in corners or in tight areas between furniture and walls. or any other weird geometry. ie: I have a wire shelf. Roomba doesn't fit under it but its easy to use a stick vacuum to get between the wires and to the floor.
And this is before we get to the limit on suction and capacity in that form factor.
The roomba isn't the only possible form of robot vacuum. There may be other options for a design that isn't general purpose but eliminates those issues. Perhaps we should just install elevators or dumb waiters in houses (dumb waiter may be cheaper because it doesn't have to be human rates for safety, while elevators are also useful for humans in wheel chairs which at some point in your life is likely to be someone you are close enough to that you would want to invite them into your house). Likewise doors that can open themself are an option that can solve other problems (think star trek - not current technology)
1. Stairs. Roomba's can't vacuum stairs, so you still need to do those yourself.
2. Stairs, Roomba's can't traverse stairs, so you need one for each floor.
3. Doors. If you want the Roomba to vacuum the whole house, you have to have all the doors open for it.
4. Can't have anything on the floor, the Roomba will either get stuck or avoid it. But I shouldn't have to never leave a backpack on my floor if I want it vacuumed.
5. Corners. Roomba's can't vacuum in corners or in tight areas between furniture and walls. or any other weird geometry. ie: I have a wire shelf. Roomba doesn't fit under it but its easy to use a stick vacuum to get between the wires and to the floor.
And this is before we get to the limit on suction and capacity in that form factor.