Ok so I have an update:
I managed to buy a A5000 off ebay for £1100, more than half price (hope it’s not a knock off 
)
I also bought a second hand Lenovo ThinkStation P620 Ryzen Threadripper PRO 3975WX for £3000
There is no ram in there but thinking I will go up to 256GB for future proof it’s only £300 more than 128GB
Then there is the issue of Storage.
Currently there is on 500GB M.2 in there with a windows 10 install. I was going to buy one more 500GB for the linux install. Then wasn’t sure what to do about the framestore and project drive for the windows 10 partition.
Possibly get a PCIe card and raid 0 with x2 m.2 for windows and x2 for linux then sync up to a QNap. But that will be £££££
Thing is I work with another guy who’s on Nuke who also works remote so need a solution to sync with him and keep file paths consistent. Has anyone here done anything similar?