I agree with @Mark Russo that when it comes time to rent it, you'll want to do a market survey to see what rents are.

Then it makes sense to spend money on the inspections, surveys, contractor bids, etc.Financials - Review of the financials can be tricky, particularly when the current owner has not kept the books correctly.

Expect to spend some bucks to make this happen - it's no different from doing a survey on a lot you plan to build on as part of your due diligence.

I hired an attorney to draft a party wall agreement (Thanks Paul Ballew from here on BP for the referrals) and a surveyor to do the survey.

I became an expert though at wells and septic's and surveying.. to this day I can read a quad map aerials and other stuff most folks just stare at.. but now you have google earth its all right there.. 

The lender will use the appraiser market rent survey if vacant. 

They track cap rates across various markets and for different types of properties, but their service requires a subscription.CBRE Cap Rate Survey: CBRE regularly publishes a survey of cap rates across the United States, which can be very informative.

Then it makes sense to spend money on the inspections, surveys, contractor bids, etc.Review of the financials can be tricky, particularly when the current owner has not kept the books correctly.

Purchaser has option to pay off after year five (5)A single purchase price and financing term must be elected by both seller and buyer before the LOI is effective; the above terms are customizable to fit the tax and financial desires of the seller. 1)Insurance Documents 2) Environmental Report 3) Property Condition Report 4) Previous Title 5) 5 Year Loss Run Report 6) Rent Delinquency Report 7) Electronic Building Plans (Any) 8) Past 5 Years Major Capx 9) Previous Survey 10) Current Rent Roll 11) 3 Years Trailing P&Ls 12) Property Tax Bill 13) 3 Months Utility Bills 14) List of Personal Property 15) Copies of Service Contracts 16) Access to All Leases Deposit: If there is a balloon payment in year one per the respective price and financing terms, $5,000 initial deposit will be paid to Seller within 3 days of effective date.

In my market, a 4 question survey is encouraged.