How much does a 10ME 20TE PBO of a Naglfar and Nidhoggur go for? and how long to research from scratch to max?

Just want to know what a max researched Naglfar and Nidhoggur PBO go for and also how long it would take to buy them from scratch and them research them?

Is it cheaper to just buy a fully researched Nidhoggur and Nalfgar BPO than researching my own because of how long it takes and how many there are floating in contract? What do you think a fair price is and what do you think they are going for if there are too many?