Your carpet is going to be in two pieces: front section and rear section. Once you get your seat and the old carpet out, throw the new carpet onto the floor pan to get oriented with the way the carpet has been shaped in relationship to the floor. Once you have a feel for the shape, take it out and match it up to the old carpet. Start with the front section leading edge and trace/cut the shape of your old carpet's leading edge onto your new carpet. Don't trace/cut anything else from the old carpet. In other words, once you've got the leading edge traced/cut, don't go back to the old carpet - custom cut everything else.
Your process is going to be: fit, fit, fit, fit, cut, fit, fit, fit, fit, fit, fit, cut... Get it? LOTS of fitting, little bit of cutting as you go. If you try to cut it all out and then drop it in, you're f'd.
The dash reinforcement support on the inside of the driver's side footwell is a *****. Once you get your carpet with the leading edge trimmed and the hole for the dash reinforcement support cut out, move the carpet into position and bolt the support back down and it will give you something to pull against as you work backward. This front edge is probably one of the most important cuts because it sets up how everything else is positioned. Take your time and be careful.
After everything is done front to back and you are ready to put your trim panels back on, the last thing you should cut is the sides around the pillars and door sills. Test fit your pillar covers as you trim or you will over cut. Don't guess and cut the width before you've done everything else or you WILL cut the carpet too narrow and then your trim won't cover something and you'll be pissed you just ruined your free carpet set.
You can use the seat bolt holes and rear tie-down bolt holes to locate the carpet as you work back. You can stick an awl or a screwdriver through the carpet and into the holes as an "extra set of hands". If it doesn't seem to fit right you can pull the awl out and reposition and nobody will ever know you punched through - it leaves a really tiny hole in the mass backing.
Remember, you can always cut more, but you can't "uncut." Don't overcut or you're screwed. Keep lots and lots of razor blades and utility knife blades on hand and change frequently. A few small cuts and throw the blade out and get a new one. Nothing worse than trying to hack through mass backed carpet with a blade without a virgin edge.
It will really help to have an extra set of hands. $200 is a good price - unless you want the experience or simply don't have the money, pay the $200. It will probably take you several hours to get all the seats out, remove all the trim, pull the old carpet, and trim your leading edge to start, and then a couple hours to get everything set and put back together. If this is your first carpet job, it may take you the entire day to do it right especially if you are by yourself. This isn't like carpeting a Chevy Sprint (my first carpet job). These vehicles have a lot of carpet in them.
Good luck and if you want someone to call if you get stuck, PM me and I'll send you my number. I'm not a soft trim guy by trade, but I've done 5 auto carpet jobs so I'm not a complete noob.
-B