Naples has a wonderful array of terrific consignment shops offering great values. Many are located on 10th Street just east of 41 near downtown or all along US-41 Tamiami Trail. Some are run for-profit, some are run as not-for-profit. I personally prefer to shop at the not-for-profit consignment shops as not only do I get tremendous value but also have the opportunity to support great causes as well.
If you want new furniture, places like Rooms to Go, Haverty's or Ashley's offer inexpensive options.
No matter which path you choose, ask yourself first, what is the intended use of your apartment? Is it only for your own vacationing pleasure, or do you plan on renting it? If you plan on renting it, before embarking on an investment in furnishing your new place, I recommend you consider closely the costs and possible rents associated with annual or seasonal renting.
We here at NaplesFloridaVacationHomes.com specialize in managing vacation/seasonal rentals and would be happy to discuss further if you like.
Best of Luck to you,