If you are primarily going to do portraiture and environmental portraiture...close to your car, you can't beat the convenience of a monorail, such as those made by Sinar and Arca and others. They are easier to set adjustments, they are modular so you can use long rails for long lenses, and short rails for short lenses, and many have geared movements that are solid and stay put. I do a lot of "far from the car" stuff, and for that I use folding field cameras, but that is because I have to haul the stuff a distance.
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