For hobby purposes I am looking to purchase a manual vertical mill. What would be good machine (bridgeport or equivalent quality) to get with intentions of CNC retrofit in future? I see there are different types of bridgeports. Are certain ones more challenging to modify?

This will be hobby in my home with very low cash flow. I figure I can add onto it as I see fit. This will avoid having to make larger investment at one time that I cannot do. Any comments appreciated!