You must know the rehab budget and nail the ARV (it can not be a guess or estimate, it must be based on actual sold comps in your area.

Go watch some sales, see who gets the property, follow the eviction of whoever is squatting there, see how they secure the property, and fix it up, estimate on your own, talk to them, maybe get a job working for them

I estimate 350-500K in repairs and the ARV based on conservatives numbers at 8% cap is around 1.6 million.I have been "winging" it on my previous buildings to an extent but all of them turned out great with excellent cash flow and big forced appreciation. 

Back of the napkin, you can estimate them like so:Purchase price (or assessed value, whichever is newer) x .06 for a rental x millage which is often .45 or so, depending on the county and district. 

HOWEVER, today I just received an updated Loan Estimate with a $1260 reduction in the lender credits. 

While trying to estimate the home owners insurance, I ran into two companies telling me they won't insure the property because it is in fire risk area.

Then they tell me to expect a call from one of their property managers regarding the work.Days later I get a bill for $1850 from the property management company and it says the property manager called me and I approved the work.The thing is, the property manager never called me, no one ever gave me a quote (only an estimate), and I never approved this expense, and yet they did the work and sent me the bill anyway.What should I do?

Make sure that you're being extra conservative in your estimates and the money still works.

I'm estimating an evg rehab cost in the 30-50k range.Are other Phoenix investors experiencing this same things?

Choose another contractor for an estimate for a new system like you already have.