IMHO, PnP tends to run more expensive than DIY. Pick up a tank. Build your stand. Build your sump from a used smaller tank. Pick up high quality equipment for MUCH cheaper on the for sale board here, on craigslist, or another reefing forum.
Your local reef club most likely will donate some chaeto to start your tank.
It's extremely important to know exactly what you're stocking your tank with. After your tank has cycled, slowly add your less aggressive fish first, then your most aggressive fish last.
You can spend as little as you want or as much as you can't afford. Regardless of which direction you choose, make the right choice first or you'll pay for it many times over. The most important aspect of this hobby is to enjoy it. Bad purchases and rushed decisions take away from your enjoyment.
And I most definitely agree with Mushu. Buy your wife a fish and she might become invested in your setup!