HCP, this is a case where if you're in for a penny, be in for a pound.
If you're going to replace the vanity, toilet, bathtub surround, etc. in your bathroom, go ahead and gut the bathroom to the studs. See what's behind the walls, check the condition of the plumbing, electrical, etc. Buy the most powerful exhaust fan you can find (I like Panasonic models) and put it on a timer so it can run for 20-30 minutes after every shower. Gutting a bathroom will give you the opportunity to properly waterproof the bathroom with concrete board, a waterproofing membrane, mold-resistant drywall (w/o paper) etc.. It will also ensure that you put down a subfloor that stiffens your joists enough to handle the weight of the tile, so they don't crack. Finally, it ensures you never have to deal with mold or rotting--waterproof products have come a long way in the past decade alone.
With the kitchen, you HAVE to check the condition of the drains and plumbing, make sure you have the proper number of circuits, your vent hood is powerful enough, the drain venting is properly done, etc. In a kitchen, electrical code states you have a MINIMUM of five circuits, and usually more. They should all be GFCI, although it's not currently code. Here's how I would wire a medium-sized kitchen:
--refrigerator (dedicated @ 20 amp)
--range (electric dedicated @ 50 amp, gas @ 15 amp)
--dishwasher (dedicated @ 15 amp)
--garbage disposal (dedicated @ 15 amp for smaller gd's or 20 amp for larger)
--microwave (dedicated @ 20 amp)
--small appliance (two circuits @ 20 amp)
--lighting (@ 15 amps)
When was this place built? How many renos have already been done? What was the quality of those renovations? Those are the questions that will haunt you until you answer them.
And whatever you do, CALL THE CITY AND ASK IF YOU NEED A PERMIT. Permitting is not meant to screw you, but protect you. An inspector will come in and ensure the job was done to code. And speaking of code, MINIMUM CODE SUCKS; always go a little bit better.
My point is if you have $5K to spend on a bathroom and $8-10K to spend on a kitchen, you're better off waiting until you have $10K to spend on a bathroom and $20-25K to spend on a kitchen and do the project right. When you gut, you can also change the configuration to any way you wish. It's well worth the extra money. Otherwise, just spend a grand or so and paint each room, update the faucets and light fixtures and keep saving for the day when you can do it properly.
Remodeling takes time, planning and money. If you don't know what you're doing, hire someone who does. Have a few designers come in and give you ideas. Buy some books about how to remodel. Your kitchen and bathrooms are the most important rooms in your house for re-sale; a bad reno can actually diminish the value of your property.
P.S. Don't use Home Depot for contracting services. Find a licensed and bonded contractor and ask them for a reference list of at least 20 references.