Turn off the main water supply to the house, and in a convenient location, cut the hot and cold water supply pipes for the bathroom. Also cut out and remove all the existing water lines and fittings in the bathroom. Finally, cut out and remove the vent section leading to the sink and the main stack 5 in. below the vent tee. Stuff rags into open drain lines to keep sewer gas out of the house.
The cheapest route of all also typically the one that takes the most time: doing all or most of the work yourself. A very (very) skilled DIYer with plenty of time and a group of willing friends and helpers may be able to finish a bathroom remodel nearly as fast as a general contractor, but very few homeowners fall into that category. And there is the issue of quality: good contractors will do the job professionally, while many DIY installations will be recognizable as the work of an amateur.
The wall-hung toilet’s supply line must have a male adapter with a temporary galvanized cap. Check the instructions on the toilet to get the proper location. Routing water supply lines is different in every bathroom, so you’ll have to adapt runs to your situation. But run the plastic drain lines and vents before starting any supply work. It’s much easier to route water supply lines around drain lines than to route drains and vents around supply lines. The same thinking applies to electrical work: Wait until the water supply work is finished before wiring.
Time to jump into your DIY pants. I am going to start off with the easiest and most prevalent DIY project around the house. Believe it or not, new paint can transform your bathroom from 1980s drab to 2010s fab. Whether you go bold with dark blue or casual with stripes, new paint will not only give new life to an outdated bathroom, but make it feel larger as well.