现在的contingency是这样：
-Lien waivers to be signed from both xxx（GC1） and xxxx（GC2） and provided to buyer.
-If any liens arise after the close, they will be seller xxx xxx's responsibility.
-If above terms agreed to, buyer hereby Removes any and All Contingencies.
I cannot advise without seeing actual contract content. For example, lien waivers are helpful, but the clause did not specify the actual content of the waiver. GCs could sign a meaningless lien waiver doesn't waive anything, and the seller can say condition satisifed, waive your contingency.
The promise that future lien are seller's responsibility is an empty promise. Like I said earlier, mechanics lien usually can only filed within 3-6 months after service, (check your state law), it is worthwhile exploring the seller put some money in an escrow for that duration, until deadline for mechanics lien expires, to actually back up his promise with money.
Of course negotiating these clauses requries a local attorney. I don't think you should skip actual legal service on this complicated issue.
