Mix it with paint of the same color in a lesser sheen would be the only way I know of.

@mcarroll16: "Eggshell on a ceiling works if you've got a good even ceiling surface...If your ceiling has a poor drywall job, the eggshell finish highlights every bump. Yup. It would also depend on how the room is lit. If the room had recessed lights which didn't illuminate the ceiling directly, a flawed ceiling might look acceptable while it wouldn't if lit directly. My kitchen ceiling was repaired by a pair of clowns after a water leak. It looks terrible on close inspection but since the room is lit only by recessed lights, the flaws aren't noticeable even though it's painted with semi-gloss.

I agree with acm regarding the maintenance. But there's a little more to it with the actual sheen. It helps to know the exact brand and which line of paint. For example - Benjamin Moore Chantilly Lace in their Regal line or the Scuff X line? (or ??) As far as the sheen for the ceiling - flat is most often used because of (1) it doesn't reflect the light as much, and (2) flat hides imperfections better. Unless you pay extra, drywalled ceilings aren't perfect. We recently finished a 2500 sq ft remodel of our lower level (with kitchenette). We used all BM paint - BM Muresco Ceiling (flat); BM Scuff X Matte for the walls; BM Scuff X Eggshell for the closets; and BM Scuff X Satin for the trim. (We have 15 grandchildren.) We're very happy with the paint quality. To know how the sheens compare, even in the same brand, you will have to read the TDS sheets. For example -Scuff X Matte has slightly more sheen than BM Aura Matte. Another note, if you're painting over stained trim, sanding and priming are necessary for the best adhesion and wear. Insul X Stix is a great primer. ETA: Sometimes here on Houzz, but mostly on a few other painting blogs I follow, people often mention that Sherwin Williams paint has less sheen when compared to other paint - for example, SW semi-gloss is closer to Benjamin Moore's satin. Best way is read the TDS and get the gloss level as a percentage.

I was going with Sherwin Williams because they carry vinyl safe paint in any color desired. My painter was planning to use Luxor primer prior to duration paint. Lot to unpack. I think you're talking about LOXON masonry primer/sealer. LOXON/Duration is not the right strategy for masonry. I encourage everyone involved to ask more questions, get more info. I'm saying don't do it. It's Vinyl Safe Colors. Not paint. Sherwin-Williams, Benjamin Moore and PPG all have vinyl safe colors. Sherwin-Williams has a collection of 100 VinylSafe colors. The color codes start with VS. No VS specific color collateral besides online and in-store brochure The colors are regular SW colors, reformulated and renamed. Store has a cross-reference sheet. So you can use color chips and Color To Go Jugs if you cross-reference. VS colors available only in Emerald Exterior Latex Paint, Duration Exterior Latex Coating, Resilience Exterior Latex or SuperPaint Exterior Latex Paint. Benjamin Moore has 75 vinyl safe colors Same names/codes as regular colors Available in any of their exterior bases I am an expert on Light and Solar Reflectance Values with regard to exterior application of color. Bottom line, I'd never paint an exterior vinyl product darker than its original factory color. I'd still choose a vinyl safe color, just never a darker vinyl safe color.