We are looking to sell but there is an ingrained smoking odor from previous owner's 20 years of smoking.

Once the oil smell fades, there is no detectable odor.

Bleach only removes color and odor wont kill root structure.Best is oxidation ie UVC, o3, H2o2, dry heat over 125 deg and plant based surfactant cleaner all speeds up the process and is safe non toxic.mold test maine runs $75-100 sampled by generalist sent to certified 3rd party microbiologist with quantitative test results over qualitative preferred. 30 or less CFU is expected range.if need court expert or Osha complaint hire an industrial hygienist $450-600 per report..i charge $85 ea.

This is due to "Obnoxious" odors caused by the neighbors.

The carpeting/flooring is not ready to be replaced and there is a lingering odor of pets or cigarettes.  

Hoping I can get advice on how to eliminate strong smoke odors in a bathroom.

The deposit keeps tenants mindful of minimizing damages and the monthly fee covers wear and odor mitigation.

If the smell has saturated the drywall it would be best to just pull it out and replace it rather than try and remove the odor. 

It really irks me when a city starts telling us what we can do with our properties.Do you know if there are any grumblings about doing it to Galveston proper and not just Jamaica Beach?

Once you prime the drywall, and replace urine soaked flooring, you should not smell the odor anymore.