If the other party will not stipulate to the genuiness and authenticity of the documents, you have to get them admitted through a "custodian of records" for each business as a business record created and saved "in the ordinary course of business."
Since lawyers can always get this introductory testimony but at some expense and inconvenience which the opposing party may have to pay for, the opposing attorneys usually agree to stipulate to their authenticity if not to their relevance and materiality. However, an opposing attorney knowing that he/she is dealing with a layman who may not know how to authenticate documents may not be willing to stipulate.
There is a process called "Requests for Admissions" where you ask the other side to admit the authenticity and genuiness of a document. This is high-end civil procedure. You should hire an attorney just to handle this portion of your case.
The foregoing is offered for informational purposes only and is not legal advice nor does it create an attorney-client relationship but if the answer was helpful, kindly check the thumbs-up box below.
No. Bank statements are bald hearsay. They are an out of court statement offered for the truth of the information in the records. You need to introduce these through one of the exceptions to the hearsay rule including the business records exception. You may need to bring in a records keeper from the bank.
Checks are a simpler matter. If the person who wrote and signed the check is on the witness stand, you simply lay the foundation, approach the witness with the check, ask them if they recognize the document, if that is their signature, and if that is the check that represents the transaction referred to while you were laying the foundation.
Evidentiary considerations are one of the tools of the trade for a trial attorney, similar to a scalpel for a surgeon or a baby grand piano to a concert pianist. I highly suggest that you retain a trial attorney.
This answer is provided for informational purposes only. Legal advice can only be given in an office appointment by an attorney licensed in your jurisdiction with experience in the area in which your concern lies.
The information given to you by myself above is, as far as I know, currently the law and procedure in a Florida court. (There is more to it of course). And I am sure the information given to you by Massachusetts attorney Myers is doubtlessly good law in a Massachusetts court. I suppose he answered your question because there aren't very many people in MA asking questions about MA law and there aren't enough Florida lawyers to answer all the questions Floridians ask about Florida law on AVVO.
Aside from the fact that there aren't that many of us lawyers here in FL, the ones there are of us are just not as well versed on the Florida law of evidence as Massachusetts, New York, or California, lawyers are. We need more out-of-state attorneys to help us Florida lawyers answer Florida practice and procedure questions. On behalf of all Florida attorneys, Thanks Mr. Myers!. :)