Topic: Void or Inexistent Contracts

Scenario: Don Eliseo, father of Armando, owned two (2) parcels of land consisting of 500 sq. m. and 451 sq. m. located at Antipolo City. The two (2) parcels of land were sold to Honrad at P1,000,000.00 and P750,000.00, respectively. Armando, contending that the contract price for the two (2) parcels of land was grossly inadequate, tried to negotiate with Honrad to increase the purchase price. When Honrad refused, Armando then filed a complaint for annulment of sale. Honrad alleged that the contract of sale was null and void on the ground that Don Eliseo, at that time, already had senile dementia. Honrad, on the other hand, contended that Armando had effectively ratified both contracts of sales, by receiving the consideration offered in each transaction.

Question: What remedy does Armando have, if any?