Just moved to Chicagoland area and looking for some good short term rental Air Bnb zips close to downtown.

If you stay in the 76549 and 76542 ZIP Codes, you are less prone to crime. 76541 is where you want to stay away from if you are avoiding high crime areas.

Going by zip code won't help you. 

80k all in on a single family is on the high side. depending on what zip and part 

I thought so much... once you've closed on this one I suggest focussing on commercial size MF - not just in your zip code - to scale faster.

You are going to want to make sure that you have these important coverages.Dwelling coverage (replacement cost)Loss of rents (minimum 1 years worth of gross rent, I prefer 18-24months) Premises Liability (minimum 300k, I always suggest 1mil)Rates are very dependent on zip codes.

Is there any specific zip codes in these areas that would be the best to start to look into?  

It heavily depends on the zip code/neighborhood as some communities are more vocal than others.

What has work for me in the past is just picking a few target zip codes pulling how many cash sales are in that area then deciding if It would be a good area for me to farm numbers and start calling around to gauge motivation!

Cleveland had 7-8 of the top ten zip codes with highest foreclosure rates in the US in 2022, according to Attom Data Solutions, so take that as you will.