Should I employ a PR person to help grow our business?

I run a UK based jewellery company specialising in bridal jewellery. We have a turnover of circa £4m per annum. We advertise using Adwords, Youtube, and run active facebook campaign. However, we don't do any proper PR activity, so it is an obvious gap in our marketing strategy. I realise I could engage a PR agency, or I could advertise in the PR press and look to employ our own PR person. However, I am not clear on what my PR 'objectives' should be. I also don't know what a good result would look like, or how much I realistically need to budget for. So far, I have been skeptical of the value of PR. Realistically, we are not Coca-Cola or Panasonic, and I am not sure I have the appetite to afford the size of campaign to try to build a large scale 'brand'. Hence to date, I have focused on direct response marketing with adwords etc. Some possible avenues which might work and which I would include in the PR category is; * Celebrity endorsements * Featured products in bridal magazines * Press releases (I realise these don't generally work) * Events * Local awareness campaign in local papers As you can see, I am bit confused on the best way forward. So I am looking for an expert in PR, who I can pay to give me some guidance on this topic. Once I find a PR expert I can trust, I would like to discuss with the the following questions; i) Can PR generate a measurable increase in sales for our business type and niche? ii) What is the minimum amount I should budget to test if it works? iii) Should I employ somebody or use an agency? iv) What is the right PR strategy I should set from the start Thanks for reading!