I am not clear what "database" information is so vital and time saving that one could not create their own.
I vet comps and save by state, year, and type. I have a template that I fill out of each comp.
Then I transfer that information to a grid as needed. That takes about 2 minutes. My tables in my report calculate so bingo, I am done.
The report is a keyboard merge which jumps from place to place allowing you to type, run a macro, or insert a file.
You've demonstrated some luddite tendencies in the past Terrel. You work in a market and with a product type where volume is low, and repetition is infrequent.
A database, by its very nature, even if not integrated into any other system, insures data integrity. You confuse the term "database" with "I have my data in a way I like". They are not the same. With a modern database, every record and its multitude of variables and associated data has historical records attached. You can see who entered it, when it was changed, etc. It can be used for statistical analysis by directly accessing it with programs like SPSS.
Excel can also link to a database to pull appropriate record data as necessary and populate whatever analyses you wish.
Now, if you're working with 20 comps a year for your farms, then yes. this is perhaps not necessary.
Here in Washington, DC, I have stored over 800 comps of various types in the past year, and that doesn't include hundreds upon hundreds of condominium sales that I have not saved in database as we do not have one yet.
As has been said by the Appraisal Institute for a very long period of time, our goal is to become arbiters of data who rely upon statistics for our adjustments and market analyses.
The days of using your appraisal expertise to simply make up adjustments is coming to an end. Qualitative adjustments will work in many cases, but it is my understanding that in these days of agribusiness, farms are subject to the same kinds of analytical methods. How many chickens or heads of cattle can be raised? How many bushels of wheat?
The market for farm real estate in this case is very much regional, so there should be ample data beyond what you are using.
This is the future of appraisal.