A final footnote which may or may not be relevant: after ownership of Arlington was returned to the family, Lincoln's son bought it 6 months later for $150,000

The CPI calculator doesn't go back to the 1880s, but it is probably safe to say that this was an enormous sum: at least $5M in today's terms, in turn even more due to the relative lack of cash in the gold-backed era: 75000 ounces of gold = $8.5M+

Thus Lincoln's association with Arlington/Robert E. Lee's/Custis' ancestral estate is manyfold. Said son is also buried there.