I think how cheap the process is would depend on what you define an artificial womb to be.
If you are thinking a large plastic tank with artificially created biological fluids that exactly duplicate what is going on in a mothers body, then it would be pretty expensive.
On the other hand, you could go with an artificial womb cloned from a sample taken from the mother's womb. The sample could be grown into a large collection of cells in a facility then popped into a 3D printer where the cells would be printed into a cheap mass produced artificial womb casing that would contain the blood pump, blood oxidizer, hormone regulator, etc. The point being there wouldn't need to be any customization of the womb casing so you could take advantage of economy of scale to bring down the price. Also, the casing could be made to be reusable by simply removing the old biological material and sanitizing. 335
No need to buy an expensive piece of equipment if you can just rent one for 9 months.
By growing the artificial womb you could eliminate:
* Cheap genome sequencing
* Big-Data analysis of blood chemistry monitor matched with genome sequencing
* Creation of a viable artificial placenta
The baby would create its own hormones so no need to duplicate those, but you might need an implant in the mother to duplicate her hormones and a artificial hormone pump in the womb casing to deliver those to the baby.
A ultrasound fetal heartbeat probe wouldn't be very expensive. The expensive part of that is the specialized computing equipment that goes along with the ultrasound monitor, so I would imagine that you would only need a few monitors in the facility and you could easily swap them between the built in probes in the womb casing.
You would need a implantable device in the mother to monitor her blood chemistry if you wanted to match it, but it could be pretty dumb and could be slaved to a device like a smart phone to process any data and send the signal on, which would save on costs.
Placental monitoring would be cheap since you could literally grow the womb around a fluid port that would allow someone to easily take a placenta sample
As a bonus you could have any additional monitoring of the mother that might benefit the baby be outsourced to a smart phone application. For example, you could pick up the mothers heart beat and voice and have that broadcasted over to the baby in the artificial womb.
Edit: It just occurred to me you wouldn't need a ultrasound monitor at all. Since you would have printed the womb into a casing you could simply add pinhole cameras around where the womb material will be printed and have the baby on video surveillance 24/7 for dirt cheap. 335