Regardless of the fact that it's not an inquiry by a credit issuing company, it's still an inquiry and will be treated as such. The only time the type of inquiry matters is when there are special circumstances such as Chase and their 5/24 rule (although even then, it's not about the inquiry per se).

If you think your credit is in such a state that you need to wait 90 days between inquiries, then you should wait.

With that said, I've been able to get some property management companies to waive the credit inquiry by offering a copy of my report or by showing them my score as provided by Barclay, Discover, etc.