“I like to have a martini, two at the very most. After three I’m under the table, after four I’m under my host,” wrote Algonquin Round Tabler Dorothy Parker, whose former Bucks County estate is for sale. Break out the gin, then, and imagine yourself as said host at the $3.85 million Pipersville property, which includes a roomy stone house, pool, pond and horse barn on 20 acres. If you can’t afford it, Parker herself would advise you to somehow get the place anyway: “Take care of luxuries,” she once noted, “and the necessities will take care of themselves” (Deedee Bowman, Coldwell Banker Hearthside; 215-862-0300). … The city’s most stylish house is about to come on the market: the Chestnut Hill manor-gone-mod of Anthropologie president Glen Senk and his “coolhunter” partner Keith Johnson. (They’re not leaving — since they spend much of their time traveling for work and also have homes in Manhattan and Palm Beach, they just want a smaller Philly residence.) The turn-of-the-century house, which looks as gorgeous as an Anthropologie catalog, has been featured in shelter magazines and on TV. The real question: Would Johnson and Senk throw in their furniture and artwork, and the phone number of their gardener? And themselves, as occasional guests?