Buy a cheap waterproof sheet if youre really worried about him peeing the bed..
It does take a while to get used to a new dog of any kind you have to learn their language the motions they use for telling you they are unwell need to go out ect.. So the advice to treat him as a puppy and allow him outside often praising like mad and getting that routine established is good advice..
Accidents will happen but it shouldnt be a deal breaker. Objects can always be replaced a life cant..
another question has any one had success wit a dog trainer tat would break the marking habit to rid of the diaper??its not going to happen because of the distance we live very far from each other an interstate drive but thanks any way