Does one make a shehechiyanu on buying a new (expensive) vacuum cleaner? If married and both benefit from it would it be a hatov umetiv? If yes, how long does one have to make the bracha?
It is hard to judge your personal situation without knowing it, but in general a vacuum cleaner is not considered a purchase that one has such joy on it, to make shehechiyanu or hatov umeitiv. You can take a new fruit, and make the bracha on it, and have the vacuum cleaner in mind. Alternatively you can say the bracha without saying H-shem’s name. You are allowed to make the bracha as long as the original joy of the purchase is still there.
O:CH 223-6, M:B 223- 11, 15, Sharei Habracha 20-26 ftnt. 79, Poskim