Do I need to pay for engineering, 3D and permits?

[Toxophilite]

A deposit is somewhat like an engagement ring; you’re not married, but you are indicating intent to marry.

If a person proposes and offers a ring, don’t accept unless you intend to get married.

When a company asks for a deposit and you are not ready to commit to a contract, don’t give the deposit.

Deposits should always be considered to be nonrefundable unless otherwise specified.

When I was going to build my home as contractor, I paid over $16K in architect, engineering, and some permitting work before I even razed first blade of grass. Entire project got sidelined in favor of custom builder who could turn-key the project much easier on me and more cost effective. When I met with builder, and knowing what pre-construction costs were, I forked over $5K non-refundable deposit before signing build contract to cover what they had to do in engineering and design and considered it necessary on their part to cover them and a deal for me. That $5K was already built into the job cost, so if I went with a construction contract, such was credited. If not, my choice on lack of refund.