In the upstream oil business we would routinely buy mom and pop small businesses for a multiple of EBITDA based on the stability, scalability, and transferability of the revenue.

Plus, as Mark said, if you only have a little bit of cash now you don't want it to be tied up in some tax lien for 12-24 months while you wait for the court case to play itself out.Are tax liens scalable?

One of the most difficult aspects of flipping houses is the scalability.  

Changing filters yourself is not scalable. 

My initial thought was to network with several wholesellers to enlist their services and leverage their scalability of searching, marketing, and purchasing.  

This solution is not scalable once we have large number of units. how other people are doing here?

I'm not a huge fan of condo investments myself (your investment is at the health and whim of an HOA) but maybe that's a more scalable option for you.

It avoids the CA franchise tax, is scalable so you can add multiple assets under it while benefiting from the liability minimixation structure of child series' , and it can streamline your operations by using one set of books, bank account, etc.

My company has a VoIP system that's scalable for any sized business.

No building permits (Zoning of course); depreciate over 7 years; ships already erected or on-site; installed with forklift; lower property taxes; leasing & financing opportunities; portable; scalable; & so forth...I'd look into Universal Storage Containers.com or Bos Containers or even e-bay & Craigslist.