In case you want to become a bathtub repair through apprenticeship, you will have to approach the local plumber's union, who can help you to find a professional plumber willing to hire an apprenticeship.
Examine the washer and replace it with a new one. Also replace screws in water line repair case they are old and damaged too. The new ones you buy should be durable and of good quality.
If you need to add copper pipe make sure that you clean the old and new pipe by using sandpaper, inside and out. If it's not clean the solder will not flow into the joint. Another tip is to not over wrap the mail threaded pipe with tape, this can cause a leak. Twice around should be enough. Also, don't over tighten it.
Getting advice from someone who has not made any money online is like asking a plumber to shoe a horse when they have never done so. Why in the world would you do this?
The water line repair most likely damaged your electrical outlets and lighting fixtures. Have a qualified electrician come in to evaluate and repair the electrical.
Find the right plumber in Washington DC could sometimes be difficult. There are so many to choose from that you may sometimes be led to wonder if you have made the right choice. The first thing to make sure when in DC is that you find someone who is within the vicinity. This will make sure that you can get in touch with them easily and have them reach you instantly.
The plumber you hire does not normally do heating but will do hot water heating or in floor heating in the house. Some places you can use the water heater for both domestic hot water and for in floor heating if the heating is a secondary heat. Check with your local plumbing codes on this to be clear.