Land dispute - Land owner vs Tenant

I would like to seek your advice on our case, where we want to sell our 4.5 hectares agricultural land (with coconut trees and own water source) @500K pesos only. Said land was inherited from my father before he passed away. We decided to sell the land due to the following reasons:

1. We cannot monitor said land because it's quite far from where we currently live.
2. Very low income. We relied to whatever amount given by the tenant.
3. We want to use the money to start a family business.

The problem is that the tenant doesn't want to leave despite we offered them P15K as gratification (knowing that they benefited a lot from the land and its products for several years already). They were asking for P50K which can't be because 500K would still be divided into four shares (mother, sister, brother, and I).

We don't have a choice but to bring this matter to court if they insist to stay. What would be the appropriate case/grounds to charge? Can we charge them with illegal squatting? How about trespassing? What is the local eviction procedure here in the Philippines? Please guide me what steps to take.

Thank you very much.

Ask ko lang po kasi yung tenant ng mother ko sa province ayaw po umalis dun sa property namin at
nagtayo pa po sila ng bahay na bato within the property. anu po bang dapat gawin tungkol dito??? matagal na po kasi kaming hiundi nakakuwimn sa province dahil malayo so hin di namin na monitor at pagbalik po namin dun ay ganito na po ang nagyari. help. thank you