Your Dogmar is a real gem. Call me if you have ANY instinct to sell it. A big bottle of Mark, for openers
The effect of 'flare' is to make the very darkest step of the scale dark, dark gray instead of black. It never bothered Weston, Strand, or Adams. Gosh, this is a fine, fine, lens. It will shoot wide open VERY nicely. Open sky, at the end of the day, great. Window light ? Fantastic. You've landed on your feet. JUST DON'T EXPECT FLARE AND SOFTY CRAP. You now own a perfect lens, even better to be carrying on the family tradition.
With all respect to our beloved Apuggers who are besotted with their Heliars, when I owned a couple shoeboxes of Heliars, I happily sold them and kept the Dogmars. If you decide to renew the R.O.C., do a search here for Bellows Manufacturing in Birmingham UK. You've done good.