Welcome to Just Answer.
Sorry to hear about your problem.
The best choice would be to remove as much of the small drain piping as possible and upgrade to 3 or 4 inch PVC. This would solve many problems, but I know it may not be in your budget.
The next best thing is to use a tool that can scrape the pipes; a plumbers snake/ auger that has the correct size fitting on the end can help cleanup the pipes. You can rent these at a local rental shop or have it professionally done by a qualified plumber.
If you have any cleanouts, they can help. You will need to remove the end cap by twisting it off with a wrench. Once the cap is off you can use a plumbers snake/ auger to clear the clog.
Another approach you can take, for removing clogs but not so much for cleaning the pipes, is to remove the trap and use a product called the "Drain King," found at your local home improvement store or hardware store; they work great at unclogging drains. It comes in different sizes for different drain diameters and you simply attach it to a hose and slide the hose down the drain pipe or at removed trap, as far as it will go. You then turn on the hose and it builds up pressure to the point where it releases in several bursts, expanding and contracting. You can clear one obstruction and then push the hose further to get to others and they are only around 10 to 15 dollars.
Here is a short video on how the Drain King works, but ignore the foreign language.
Chemicals often do more harm than good on the plumbing, so I would stay away from them.
If you need further help or clarification on this answer, please do not hesitate to reply to this post.
Thanks for asking your question at Just Answer.
Best of Luck, Brian
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