I want to buy a house for 69,900 dollars? How much down payment should I put down?

shoot for 20% down (14,000). this will keep you from having to pay additional for private mortgage insurance (pmi)

Maybe. 1. It depends on what you mean by bad credit. In some cases you will not qualify for anything but a hard money loan if you have certain types of credit issues. 2. A big down payment might only be 5% or 10% more than what you would put down if you had good credit. Note that the days of 100% loans are rapidly closing given all the problems with such loans. 3. You can some times get the seller to take back a second. The new lender in 1st position sees the second from the seller as similar (not exactly the same but similar) to your down payment. Hence you might not be putting up that much extra. I am not saying that a seller suppled second makes sense as each deal is different. 4. On a tangent you might be able to do something to improve your credit before taking out a loan. Get all the mistakes removed. See if you can negotiate a settlement for the items that are negative and accurate. Included can be an agreement to have the negative marks removed if you pay up. 5. If you have someone who trusts you and having them provide a guarantee that you will make the payments or they will step in can work. It might be best that you delay buying until you sort out a few things. If you are in a market with falling or flat prices you are not really risking much by delaying. Buying is not the right decision for all situations. If you are not planning on staying 3-5 years it could cost you more to buy compared to rent. There are real costs to buying and later selling which you might not recover.

if you are able to, put down at least 20%, which would be ~14,000. If you can put down 20%, you can avoid the extra penalties for mortgage insurance.

20% to avoid the PMI

There is no "usual". It would be helpful if you know what your target payment is. What can your budget handle?

$14,000 20 %