I have a small car sales and car rental company, i want a website or software that will help me keep track off all car that I've sold and also separates the rental units from the units being sold. also i would like something to keep track of my clients monthly payments on cars being sold/financed through my company. also i want to be able to keep track of the days the rental car are out. also i want to able to upload documents under specific cars that's being financed/sold/rent.
note: i don't want anything public, i want this system for only my self and 4 other workers.