Mailvox: database question

Paradox looks for advice:

I have a question. What type of database software would you and the Ilk recomend for a small business? The business will be auto repair. The database entities would be customers and invoices. Atributes would be items like invoce number and car make and model etc.

All I have to say is that’s a good business in this economy. But I know nothing about databases, so if anyone has anything intelligent to offer on the subject, please do so.