This has always been a very hush hush topic from people that actually do collect. I have seen it two ways. #1 and cheapest was smooth finished concrete with floor drains poured in and daisy chained from each stall to a small pit that would hold a 5 gallon buck. That urine would have to be strained and the floor would take alot of work to keep sterile. #2 I saw at a big time urine collection facility. They had an elevated floor using rubber coated floor panels called tender foot. They are used in hog facilities. These panels are like expanded metal then rubber dipped. The deer stand on them and then below that is a full stainless steel floor that would taper and funnel into a collection tank. This is alot easy to clean up but is going to be very costly to build. Hope this helps. I collected a few of mine before but never took it very far. My advice would be, there are farms that will sell it to you whole sale for cheaper than you could build your facility and then you could private label smaller bottles to try and sell. If that works for you and you start making money then you could build a facility of your own if you wanted.
Good Luck