const regex = new RegExp('(?m)\\s*\\'\\s*(.*?)\\s*\\'\\s*(?:,\\s*|$)', 'gm')
const str = `'MLS Number\\n2201211\\nCounty\\nCass\\nCity\\nRaymore\\nSub Div\\nEvan Brook\\nType\\nSingle Family\\nFloor Plan Description\\nSplit Entry\\nBdrms\\n4\\nBaths Full\\n3\\nBaths Half\\n0\\nAge Description\\n16-20 Years\\nYear Built\\n2003\\nSqft Main\\n1500\\nSQFT MAIN SOURCE\\nOwner\\nBelow Grade Finished Sq Ft\\n500\\nBelow Grade Finished Sq Ft Source\\nOwner\\nSqft\\n2000\\nLot Size\\n115x130\\nSchool District\\nRaymore-Peculiar\\nLegal Description\\nEVAN-BROOK LOT 184\\nS Terms\\nConventional',
'Fireplace?\\nY\\nFireplace Description\\nFamily Room\\nBasement\\nY\\nBasement Description\\nConcrete, Finished, Walk Out\\nDining Area Description\\nKit/Dining Combo\\nUtility Room\\nOff The Kitchen, Laundry Room\\nOther Room\\nFamily Room\\nInterior Features\\nKitchen Island, Painted Cabinets, Vaulted Ceiling, Walk-In Closet, Whirlpool Tub, Wood Floor\\nEquipment\\nCeiling Fan(s), Dishwasher, Disposal, Gar Door Opener(s), Rng/Oven- Electric, Refrigerator, Stainless Appliances',
'Rooms\\nLiving Room\\nLevel 1\\nKitchen\\nLevel 1\\nLiving Rm- 2nd\\nLevel B\\nBathroom Full\\nLevel 1\\nMaster Bedroom\\nLevel 1\\nMaster Bathroom\\nLevel 1\\nSecond Bedroom\\nLevel 1\\nThird Bedroom\\nLevel 1\\nFourth Bedroom\\nLevel B\\n2nd Full Bath\\nLevel B',
'Garage/Parking?\\nY\\nGarage/Parking #\\n3\\nGarage Description\\nAttached, Side Entry\\nConstruction\\nFrame\\nArchitecture\\nTraditional\\nRoof\\nComposition\\nLot Description\\nCorner Lot\\nIn Floodplain\\nNo\\nExterior Features\\nDeck, Fence- Wood, Porch, Storage Shed',
'Central Air\\nY\\nHeat\\nForced Air Gas\\nCool\\nCentral Electric\\nWater\\nCity/Public\\nSewer\\nCity/Public'
`;
const subst = `\1\\n`;
// The substituted value will be contained in the result variable
const result = str.replace(regex, subst);
console.log('Substitution result: ', result);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions