房东保险的维修保险这块值得买么?

一个月10镑,价格比BRITISH GAS有优势,但是他们只负责维修费的500,超出部分自己付,其他维修还好,最怕锅炉出问题,锅炉的维修这个价格500够不?他们不负责每年的锅炉维护,我要不要另外花钱每年冬天前做一次维护?
这个锅炉去年刚大修过,换了一个新的主要配件,具体是什么不清楚,这个锅炉应该还可以用个5,6年的,我在考虑,要不今年不买这个10镑,在冬天前花钱做一次维护,然后明年再买这个?大家觉得呢?

看了一下具体条款,一年只让你维修三次
Plumbing and drainage
Primary heating systems
Gas or electrical supplies
Security and glazing
Roofing
Pests
Covers all charges associated with an emergency in the home including call outs, parts and labour up to a maximum of £500 per emergency.
Where the insured event renders the property uninhabitable, the cost of alternative accommodation is covered up to £250
There is No Excess and No limit on how many claims you can make.

The endorsements of this policy are

serviced at least once a year
Cannot claim within the first 2 weeks
£500 per claim 3 claims max per year.