Typical cosmetic (lifestyle) upgrades we do are better/more LED lighting, dimmers, flooring, paint, trim, solid wood door slabs in place of the hollow core etc.

Can they go by and check lights and thermostat after every showing? 

Here is a breakdown: Queen bed frame: $400 - $700 High-quality mattress: $500 - $9,000 Pillows (2-4 per bed): $40 - $120 Linens (sheets, duvet, comforter): $150 - $300 Blanket: $50 - $75 1 Bedside tables: $40 - $150 1 Lamps/lighting: $40 - $75 Art decor (2 pieces): $100 - $275 Bathroom towel racks, dispensers and soap racks: $100 - $200 Makeup mirror: $20 - $80 Hair dryer: $20 - $60 5x7 rug: $75 - $250 Small vase with plant: $20 - $50 3-ft decorative tree: $50 - $150 Two window curtains (with rods): $80 - $150 55-inch TV: $375 - $500Total cost per bedroom will range from $2,320 - $3,545 

My goal for clients is to bring additional information to light to let you think thru your options! 

My best advice is to pick the issues that are of major concern like roof, foundation, radon etc. but perhaps skip the leaky faucet or burned out light bulbs.

Lights on in several places.

And I dont say that lightly I lived there for 1 year and was managing these homes daily personally I saw it  this is not 3rd hand..

., landscaping, parking areas, lighting) can often be depreciated faster than the building structure itself.

Might as well light the house on fire

I do supply the 1" light-filtering miniblinds from Lowes (Project Source) - and yes, they get broken pretty easily, but I charge for their replacement on turnover if they are damaged, as @Kenneth Soles does.With the blinds installed, the units show better, create some opacity to thwart people trying to ascertain if the unit is vacant, and provide some privacy once the tenant moves in.