Lourna,
If you need an accrediting body and want to stay with a U.S. based AB.....
https://www.nacla.net (National Cooperation for Laboratory Accreditation)
https://www.aplac.org (Asia Pacific Laboratory Accreditation Cooperation)
https://www.ilac.org (International Laboratory Accreditation Cooperation)
are the websites I recommend to select an AB.
There are currently three with international recognition: IAS, A2LA, and NVLAP. All three are direct signatories to the ILAC and APLAC arrangements. That means that all three have been evaluated by teams from other signatory bodies and found to have similar levels of technical competence and management oversight as other signatory bodies.
L-A-B is recognized by NACLA, but not by APLAC or ILAC. That is not a bad thing, it is simply stating fact. A2LA has withdrawn from NACLA and is still signatory to APLAC and ILAC.
I recommend talking to all the ABs listed in this post and in the other posts. Ask the same questions (time, estimated costs based on scope, etc.) and compare. Download the cost sheet so you have the fixed costs already, and then the variable costs are based on scope. Get your answers before you send a check to anyone.
If you service a particular industry, see if there is a specific perference on which to use.....or NOT to use!
Hope this helps.
Hershal