Are you planning to do the work yourself or hire it out? The 'shoestring' will go farther if you do at least part of the work yourself. Vanity, sink and toilet replacements are pretty easy for a DIY'er. Right now HD online has free shipping on most of their bath products with an order over $249 plus an instant online rebate (starts at $70 off the order and goes up based on total dollar amount of order). They've got some well-made vanities with granite or cultured marble tops and undermount sinks included for very reasonable prices. They've also got medicine cabinets and mirrors.

Amazon, HD Online and Lowes all have a pretty decent selection of fixtures online, and I've found that a lot of the HD and Lowes prices are better online than in my local stores (I'm in the DC area, pretty high cost of living and store pricing to match.)

Tiling a floor's not outside of a DIYer's reach by any means - it's a messy job, but not tremendouysly difficult. IMO, tiling a wall's a bit more difficult, but again, not outside of a DIYer's reach. If you've got wall tile that wasn't finished with a bullnose for a smooth transition, you could find a coordinating border and bullnose and add it to the top of where the wall tile ends, making it a tile wainscot. Tiling a shower floor, though, I'd really recommend be left to a professional - there's just too much risk in not getting the slope right.

Wallpaper is another pretty easy DIY option for finishing off a wall and dressing up a space, and a wallpaper border at the top is even easier. Depending on how the wall tile you describe was left, wallpaper or a wall paper border might even be an option for right above the tile. this is if the tile is on the wall around the room, not the shower/tub. Above a shower/tub, I'd only suggest a wallpaper border at the top, and then only if the room has good ventilation (it may peel up, if the area stays pretty moist.)

Re the space - I've reno'd a bath similar in size, and can attest it can turn out beautiful if you carefully plan the fixtures/accessories. Check out Houzz for some great design ideas on maximizing space through clever accessories - a beautiful bath is not necessarily dependent on spending big bucks. And have fun with it - a reno is supposed to be a fun project! :-)

I would also encourage you to take some time to research and get comfortable with as much DIY as you can. You have resources like these forums, both classes and emplyees who will walk you through things at Home Depot and Lowes. If you keep the same layout, you should be able to do most or all the work yourself if you're up to it.

Look at Overstock for vanities and fixtures too. I looked at some there. Also saw some I like at a Marshall's Home Goods, but you never know what you will find. The vanity I am about to install in our powder room came from Sam's. Look everywhere. You can even look at IKEA cabinets or a Habitat Restore or other resale/salvage shop. I've seen people take a discarded dresser on the curb, switch out the top and convert it into a vanity. Being clever and resourceful also help stretch the budget.

Do you have a photo or layout diagram for more specific comments?