It really depends on where you are looking at prices as some practices quote the implants and the restorations (Crowns / Bridges) seperately which can make it difficult if you are trying to shop around.

In answer to your question about the difference between having an implant with a crown and a crown on it’s own; this really depends if the underlying tooth and root are suitable for supporting a crown.  If not then an implant would be the better option but this can only be ascertained following a detailed consultation with a dental professional.  If looked after the typical lifespan for a crown can be 10 – 15 years, but like implants they do need to be cared for.

I hope that this helps answer your question.

Regards
George Glover