I currently put contingencies on the following milestones:Contingencies (able to achieve the following milestones)Site PlanningBase MapSite Plan (End of 2021)Conceptual Site Plan (Beginning 2022)ArchitectureFeasibility Design (End of 2021)Conceptual Design (March 2022)Entitlements & PermitsPre-Application (Beginning 2022)Application (mid-late 2022)**Buyer Submits Refundable DepositBuilding Permit and Inspections (End of 2022)Final Approval to Build for purposes of a banquet hall (End of 2022)**Funding Land Acquisition General ContractorSite and Civil Work (End of 2022)Certificate of Occupancy (Late 2023)Is this the correct approach or is there a better way to structure this offer to take on the least amount of risk?

It also helps to pay attention to each unit and talk with each tenant during the home inspection.

I also run an inspection company focused on Bakersfield, but we serve all of Kern County, so I work with a lot of Bakersfield agents and investors. 

Who should I have to come look at them during inspection time?

However, you should learn and do your own diligence as well especially during the home inspection phase of the buying process. 

Show them the pictures and or videos that were taking during the pre-rental period inspection.

Make sure you understand how easy it is to back out if inspection doesn't go well. 

ValuePenguin is a good source for the relative cost of insurance by state.Operational Costs - Costs like property taxes, insurance cost, state income taxes, regulatory costs (ex: time and cost to evict), inspections, rent control, etc., have a tremendous impact on your return.

They should be able to get you some sort of pre-approval letter (of course it will still depend on inspection and appraisal from them).

If you needed meticulously calculated estimates you'ld never get enough offers out to get any deals. #2 rather than agonize over meticulous bullet proof estimations just educated guess it, get your offer in and et a signed contract #3 once you have signed a signed contract then get a professional to do the estimation.