If it is just spots, "RESOLVE" reeeally works great!
Darling Daughter, Mom got her ready fro Church, then jumped in the shower for a few minutes - came out to find the daughter (In Her Easter Finery - age 2 1/2 or 3 - had gone into the refrigerator, got out the hawaiian Punch Concentrate, opened it up in the middle of the Living room on our Cream White Belgian Pile carpet, and proceeded to pour it out on the furniture, the floor, and track it into the kitchen, the hallway, and all the way to the Bathroom!.. It is very red syrup...anyway, we got it all cleaned up (except where the foot of a table was - we didn't see it) It was a nearly new $3K rug. RESOLVE works good!
We also have an Electrolux Carpet cleaner/Floor Polisher - around $500 IIRC, it works good, but doesn't get a lot of use - maybe three times a year...not a great deal.
If you want the whole job done, why not hire the Pros - they do a great job, and they are in and out in less than half a day. They have great chemicals, and they are great for after a big party, or before you have a wedding reception at your place. They are cheaper than buying a machine, and they have experience with all sorts of stains and problems.