Are you looking at new or used? Big difference in prices.
So you  just want positioning. What then? It is a huge waste of money to have an RTK setup and only use it as a lightbar.
We are sparsely populated here so no networks to subscribe to. As for subscriptions, It is my understanding that some suppliers make a deal as the number of receivers each farmer has goes up.
I use a Trimble EZ-Guide 500 receiver. It will display heading, roll, lat, long.
In order to get the 500 to receive RTK, it needs an antenna that receives on both the L1 & L2 bands. It has to be unlocked to first Omnistar and then to RTK. Sticker price on the unlocks is $2K each or $4K to get from WAAS to RTK. Then in order to get RTK, I needed to buy an RTK base station and set that up in a position that had an un-obstructed view of the skies. Needed to be very stable also so this is the mounting point for the station and antenna:

Once you have corrections data, that needs to be communicated to the receivers in the roving equipment. My base station also included a 900 MHz transmitter so I needed to provide a tower and antenna that would broadcast the signal to all parts of my farm. I used an existing tower and mounted the corrections antenna on that:

Then once the corrections data is broadcast, the rovers need an additional radio to receive the corrections data. Several different radios to accomplish that and prices for those vary.

I started with a 500 unlocked to Omni*. By the time I got the RTK unlock, a used rover radio, data/power cable & antenna for the 500, and then an old unused base station with antenna, cable & wire to hook up to the 900 MHz antenna on the tower I was still under $10K. My base station will supply corrections data to as many receivers as I want and as far as that goes, if the neighbors wanted to use it, they'd be welcome to it at no cost because I'm doing it for myself anyways and it doesn't cost me any extra to share it.
One other item: once the 500 was unlocked to and receiving RTK, it also displays distance from the base in cm, distance south of the base and distance east of the base in cm too.