dealio - I figured out what each MS Access table did based on looking at the data. "Assets" is the main table, with most of the others just lookup tables ("Customers", "Dealers", "Categories"). You do have to understand relational databases if you want to do any significant data changes that might affect association of tables or write your own SQLqueries. I have decades of experience, so that is no problem for me. I also make backup copies of the database in case I screw up. I am writing my application in C# with a stand-alone version of Microsoft SQL Server. I am using Visual Studio 2017 Community edition to do the editing. The software is free so the only cost is my own design and development time.
Home inventory was created by modifying it from a coin and stamp application. Its table name "Dealers" means 'purchased from' in my world of home inventory. To create my own app, I need to write my own search and filter and reports, as well as data input forms. However, based on my personal needs, I can narrow down the 22 tables to about 4. That will make data entry much more clean and precise.
The only 'magic' I am going to have to write C# code for is associating images with each asset. However, whatever logic I come up with for doing that will also allow me to associate any type of file with the asset the same way (Word document, PDF, text file, etc.) Right now, Home Inventory associates PDF files to Assets differently than images. My way will be simple drag-n-drop regardless of the file type. Home inventory also creates its own thumbnail copy of each image. My app will point to the original file on my computer's hard drive.