The Graflex cameras are the cheapest option if you want handheld, another advantage (if it works and is in good condition) is the focal plane shutter, which allows you to use cheaper barrel lenses. For portraits the field cameras design is not the best though as the bellow draw is often quiet limited. The Graflex Reflex cameras are handholdable usually come with a lens of older design (you can change it do a more modern lens) and looking at the work of Dorothea Lange and Margaret Bourke White five superb results. With all older cameras with fp shutter you have to check out the camera personally the shutter can dry out, pinholes etc... The cheapest modern lens option seems to be the Symmar in the 210mm focal length as this was the main lens of most studio photographers and the market is flooded with them. Another superb and cheap option is the Kodak 7.7/203mm Ektar.
Regarding resolution LF lenses usually have less resolution than MF or 35mm lenses, it really is the tonality where LF outshines all other formats even the Mamiya 7
i totally agree with MDR
you might look into a graflex d series, maybe a super D or a tele ( took longer lenses had a bigger bellows extension )
it might have been the best portrait camera ever made! if i get rid of all my 4x5 cameras ( i have a handful of press and monorail cameras )
i would keep the series d i have. you never have to focus on ground glass and then hope the subject or camera moved you look down with the film
already loaded and never miss a beat. i have a 21cm 3.8 tessar on mine, beautiful portrait lens, sharp as nails stopped down open up creamy smooth "boo-ka"
i also use a old brass barrel on it ( and other things ) ... works on a tripod with ease, hand held with ease and if you have "graphic 23 / 22" roll film backs
you might be able to just tape them on the back and use roll film ( series d that is, super D has a graflock back i think? no idea about the tele ). yeah,
i was told not to, was told i'd never forgive myself, the focus would be off would be a nightmare and a utter waste of time .. but i have been doing it
for maybe 13 years without issue ( mainly with a graphic 23, and a polaroid 545i ) ... unfortunately the camera doesn't have swing or tilt but who knows if you are handy you might be able to modify
the lens mount to do what you want or have a lens board mount adapter that offers swing and tilt custom made ( guessing, not sure who knows )
if you need to use them with flash, you might be able to ask a repair person to mount a flash syc, mine originally had one but it was removed by the guy who sold it to me .. ( and probably put on something else )
i've handheld speed /crown graphics, used the range finders and not worried too, but i've also had to focus, close lens put film in, pray, expose too, the SLR is much easier and IMHO a better choice ...
YMMV
good luck !
john