When you have the van towed to the shop,,no start.
And you tell them that it wont start,,they will begin with the basic things to check first,,
Is a fuse blown ?
Are the plugs getting spark ?
How is the compression ?
Is the engine getting fuel ?
Based on the results of these items,,the shop will know the direction to go with determining the problem.
So,,,lets wait until these tests are done first,,,
Before you buy or have any parts installed.
Anything else,,is just a guess.