out of

out of 在这里表示的是“出于正式房契相关的考虑”的意思,另外再给你补充些知识吧：
Out of的基本用法和注意点一、out of的基本用法Ⅰ.表示“在……外”之意：
1.The chemical plant is out of town.该化工厂在城外.
2.Our factory is 4 miles out of the city.我厂离城4英里.（指在城外,离城4英里.）
Ⅱ.表示“从……里”、“从……当中”之意：
1.We should remove the machine out of the room.我们应该把这台记起从室内搬出去.
2.Pump as much air as possible out of the container.尽可能地把容器内的空气都抽走.
3.You many choose one out of them.你可以从中选择一个.
4.This is only one instance out of many.这只不过是许多例子中的一例而已.
Ⅲ.表示“接触”、“脱离”、“没有”、“缺乏”之意：1.They have got out of many difficulties.他们已摆脱了许多困难.
2.The instrument went out of order.这个仪表发生故障.
3.That machine is out of repair.那台机器失修了（或损坏了）.
4.Those devices are out of date.那些装置过时了.
5.They were often out of spare parts before liberation.*他们常缺少备件.
6.It is out of comparison.这是无可比拟的.
7.A new method was introduced are old one naturally.采用了新方法,旧方法自然就淘汰了.
8.Their workshop has run out of oxygen.他们的车间已用完氧气.Ⅳ.表示来源、原因和动机之意：
1.He copied something new out of this book.他从这本书里摘抄了些新的内容.
2.They helped you out of pity.他们基于同情而帮助了你.
3.He went only out of curiosity.他仅仅是由于好奇心才去的.
4.He made this table out of an old box.他用一个旧木箱做成了这张桌子.
5.We did this out of necessary.我们出于需要做了这件事.Ⅴ.表示“使……不……”和“使……取消……”之意：
1.We talked him out of his wrong plan.我们劝说他放弃他的错误计划.
2.They argued her out of violating the operating rules.他们说服她别违反操作规程.
二、带out of的一些常用词组举例out of balance 不平衡,失去平衡to go out of control 失去控制
out of doubt 无疑out of focus 散聚out of gear 混乱,发生故障out of operation 不运转
out of fashion 过时,陈旧out of joint 脱节out of step 不同步,不一致out of stock 脱销
out of touch 不接触out of practice 荒疏out of work 失业The axle is out of true.轴的部位不正了
三、out of用法的注意点Ⅰ.正确理解“from+out of+名词”的意义：
1.We should remove the device from out of the room at once.我们应该立即搬到室外的那个装置.
这里,介词短语“out of+名词”又作介词from的宾语.上句原意是：我们应该立即把这个装置从室外搬走.遇到这种“from+out of+名词”的词组,首先把“out of+名词”理解为“……外”,并作为一个整体概念来看待,然后早套上from（从）的意思即行.再如：
2.He is from out of town.他是城外人.
先把out of town理解为一个整体概念,即“城外”,然后套上from（从……）含义 ,故全句也可译为：他住在城外.
Ⅱ.根据有无其反义词in,into的搭配关系来选择和判断out of的含义.例如：1.This plant is in town.这个工厂在城里.
That plant is out of town.那个工厂在城外.2.They are in danger.他们处境危险.
He is out of danger.他已脱险.3.This kind machine comes into fashion.这种机器正风行一时.
That kind of machine came out of fashion.那种记起不风行了（或“过时了”）.
4.We talked him into making these experiments.我们劝说他做这些实验.
They talked him out of making these experiments.他们劝说他别做这些实验.
注：这种方法只能帮助我们选择out of 在句中的具体意义,而不能认为任何out of用法都有 in,into作其反义词.
Ⅲ.注意out of question和out of the question词义差别很大：
1.This is out of question an example of an important principle that applies to all machines.（作状语）这毫无疑问是适用于一切机械的一个重要原理的举例.
2.In the first instance,increasing the temperature is out of the question.（起形容词作用,作表语）在第一种情况下,提高温度是不可能的.