In my opinion, I wouldn't buy it if I were you. I'm by no means an expert on colonial-era currency, but the poor paper quality alone would keep me from buying it. If I were in your position, I'd wait for a better note to come along. https://www.ebay.com/itm/Delaware-M...=true&nordt=true&rt=nc&_trksid=p2047675.l2557
The 1777 dated notes are less common than the 1776 ones but are by no means scarce. Nice ones come up for sale pretty often. The note pictured has multiple problems.
I think they are collectible despite the condition. I look at it as "I have one so I wouldn't buy it" but I would expect it to be no more than $50-75.
Good price. That paper isn't as brittle as it appears but of course you will need to be careful with it. Delaware Colonials is one of my key collecting areas. I grew up there. If I remember correctly the printer, James Adams, trained under Ben Franklin. The earlier Delaware colonials have Franklin's name on the back.