I try to find their true reason for selling early on.

Not true.  

I don't know if theirs is too good to be true and actually I think the fact that they have the VA system set up to work on leads for you is a huge plus.

Purchase price: $35,000 Cash invested: $15,000 Sale price: $80,000 3/2 SFR with shop sold in 2021.

If that is true I think you're on the right track. 

2  - I often read about some wholesalers lack of knowledge and I must agree that sometimes, it is very true.

For LLCs, it’s true that many investors start without one, but with significant assets and your husband’s profession, asset protection is definitely worth considering.

Quote from @Robert Rixer: With on market deals like this, there are two scenarios: 1) you see something that no one else sees OR 2) everyone else sees something you don't That is true

Thanks What loan product are you shopping for?

Depending on how the water is getting in, there may be cheaper methods for sealing the basement walls from inside.Keep shopping until you find someone trustworthy with solutions.I would also consider going after the first contractor because they robbed you.