in may i moved my 81 yr old mother in my home to live with me. she is a heavy smoker and i knew this before hand. thing is my g/f and child cant stand the smell and i must say its getting to me also.

i cant demand she smoke outside just not fair to her. she has no intention of stopping so im searching for a decent air purifier to buy. i read about neg. ozone and hepa and all that stuff. can someone break it down to me and suggest a unit to buy? looking to keep it under 400$