How long to get a return on remodel for a rental?

[Roy Kwak]

First post!  Hello BP!

Sorry for the noob question but I can't seem to string together the right search terms to get the answer I am looking for.

Here is the question...followed by the backstory.

When investing in upgrades for a rental, in what amount of time do you guys expect to recoup your costs (understanding that after that point, the forced rental appreciation is all profit assuming the upgrades do not lose value)?

Backstory: 

I have a rental (2+2) condo in Century City (Los Angeles) which is a relatively high-end rental market.  Maybe I've been watching too much HGTV but I would like to remodel the kitchen, bathrooms, and put in hardwood (engineered) floors and new appliances.  The decor currently is late 80's and Berber carpet.  As is, I know I can rent it for $2800-3000.  I am hoping to push the rent up to $3300-3500.  What time horizon do you guys use to determine the value of the upgrade...i.e. if I spent $15,000 but was able to push the rent up $500, then I could recoup my costs in 2.5 years and assuming I didn't have to do any more upgrades for the next 10 years, I would pull in an extra $45,000 in rent over that time.  To me, it seems that for upgrades that will last about 10 years...I should be willing to breakeven at 3-4 years?  What do you guys think?

Also, I'm thinking of hiring a designer to help with the project...am I wasting my money?  I have two kids (including a young baby) at home and just don't have time to learn/research this stuff right now...wish my tenants were moving out in a  year!  I guess life waits for no man.

Thanks!

Roy