If this a 3.5F in good condition and has a Fleenor sticker dated within the last year or so plus the documentation of what was done it will go for $1000-1200+. Selling for that, buying a decent Rolleicord and pocketing the difference is not insignificant especially since the OP says he rarely if ever uses the 3.5F.
SOLD! for $1200 sight unseen. Will you be paying with PayPal?