Earnest Money

I got into an agreement with the daughter of a lot owner (the daughter being the legal representative and the latter was already residing in the states). To signify my true intention to buy the property, an earnest money amounting to P20,000.00 was offered to the would be owner(thru the daughter). The title was still to be transferred to the owner. The agreed price per square meter was P800.00. The transfer of title only came to its fruition in 2010 and the owner knew was I still interested. The owner contacted me to offer the same lot but with a much higher price per square meter. The price offer is P2000.00/sqmtr.
Can I still demand for the original price which was P800.00 since the agreement with the earnest money took place way back in the early 90's?
The owner wanted to sell the whole lot to me but I told her that I am sharing it with my brother. I will purchase half of it and my brother the other half. During this time there was an occupant in one of the portions of the lot that the owner had a hard time evicting. Since then we just waited for the owner to update us. Later we found out that portions of the lot were already sold to other people also at P2000.00/sqmtr without informing me although part of it according to the owner was reserved for us. Although all of these are verbal, whar are our rights especially the agreed price of P800.00/sqmtr? I hope you can reply asap because I need to contact the owner anytime soon and I need to be prepared when I talk to the owner.
Thank you very much

in my opinion, you can no longer try to enforce the contract for the old price because oral contracts can be enforced only within 4 years.