The Shulchan Aruch in OC 539:12 singles out purchasing a house as more stringent during Chol HaMoed, as it is generally public knowledge.
Even for regular items, if they are not specifically required for Yom Tov and Chol HaMoed itself, a significant loss is necessary to permit. If the financial risk is minimal as you imply, it is difficult to allow this case. Preventing hard feelings is a very worthy cause, but I don't see that it justifies purchasing a house Chol HaMoed.
Of course, if there is any risk that the delay could lead to the deal falling through or concrete financial hardship due to the other side's intransigence, there are significant grounds to be lenient.