CA has the highest sales tax rate in the country.

Are you basing this solely on what you can afford, or what you intend to make on it, or your target sale price? 

You have to be ready to make 3-6 months of payments on the mortgage yourself after they stop while you try to foreclose/evict them.

Never had a pure wholesaler approach me for this service ..

The worst part is they refuse to help me get the account back, quoting their terms of service and stating they are not liable for any issues with my account. 

Which makes my answer, as opposed to yours, applicable.Especially since I qualified mine by adding "...unless she adds more real estate work"Your argument reminds my of an old joke:- Doctor, will I be able to play violin after this surgery?

In short - if you aren't licensed to do the work -  your services aren't going to satisfy the permitting agency.  

If they won't pay, end their lease and deduct the cost from their deposit after they vacate.P.S.

Owners mistakenly ASSUME all PMCs offer the exact SAME SERVICES and PERFORM those services EXACTLY THE SAME WAY, so price is the only differentiator – and they often select the first PMC they call!

If she fails, I would go after her for every dime owed.