"The Sanity Inspector" wrote

I've got seepage in a corner of my basement. It's right under
a frequently-clogged downspout, which spills into a planter made of
railroad ties, which hugs the water right against the house.

I would eliminate the railroad ties, water is supposed to flow away from
the structure. Proper grading away from the foundation may be the solution.

I would rectify this situation, before getting involved with waterproofing.
Surely, one of the waterproofing companies mentioned this to you. OTOH,
they probably wouldn't if they're not honest.