Cheap non intrusive way to make a room smell good?

Emm-in-a-pickle

I hate aerosols of any type, also gave up on oil burners a while back. As for shake & vac, my late hubby liked it but it gave our dog dermatitis!
I now rely on a jug of dried lavender on the landing window - scent lasts forever - plus a few pots of hyacinths in season, then a pot of Greek Basil when in season, and when there aren`t living things in pots a damp duster with a good dollop of Zoflora wiped on a few surfaces, just change the zoflora type as the fancy takes me.

DigForVictory

Remove the teenager.

Remove all furniture & sling the "hidden" packets of part-eaten food, the forgotten socks & other garments, and anything that does not hold its form when prodded with a coffee stirrer.

That apart, a really thorough hoovering & leaving the window open all improve matters. Ongoing nice smells are a matter of taste & anyway leaving a breadmaker in the bathroom causes all sorts of confusion (not least how is it being powered).

Cheat. Set bread to bake an hour before you expect visitors, or make really nice coffee, or put cabbage on to boil (tastes vary). So long as a place is Clean & aired, it'll usually smell OK but to smell good is always going to be trickier.

Best of luck!