You might consider (1) using form rules to hide/show sections on an individual form and (2) create secondary forms to collect various related fields. Certain types of applications like insurance forms, loan forms etc can have an unending list of fields to collect as they ask everything under the sun. While the normal suggestion is to create child tables as Mark suggests this could get complicated in cases (like yours) where there are a lot of fields to collect.
Another suggestion is rather than create a child table for each of your 75 categories, you might be able to create fewer child tables if you abstracted the child tables to model a "feature list", "amenities list", "upgrades", or "pick list" rather than very specific child tables such as kitchen, bathroom, garage etc.
More than likely you will have to use a combination of (1) multiple sections, (2) multiple forms and (3) multiple child tables to get to a sweet spot balancing convince of data entry / navigation and performance.